appsec.fyi

Authentication Resources

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A curated AppSec resource library covering XSS, SQLi, SSRF, IDOR, RCE, XXE, OSINT, and more.

Authentication

Authentication is the process of verifying who a user claims to be — typically through passwords, tokens, certificates, biometrics, or hardware authenticators. It is distinct from authorization, which determines what an authenticated user is allowed to do, and the two failure modes are different: a correctly authenticated user can still be a victim of broken access control, and a perfectly authorized request can still come from a forged identity.

Modern authentication relies on layered standards: OAuth 2.0 for delegated access, OpenID Connect for federated identity, SAML for enterprise SSO, JWT for stateless session tokens, and FIDO2/WebAuthn for phishing-resistant passkeys. Each of these has well-documented attack surface — OAuth redirect_uri bypasses, SAML XML signature wrapping, MFA fatigue and AiTM phishing, session fixation, and credential stuffing remain among the most common root causes in real-world breaches.

The shift toward passkeys represents the biggest practical improvement in years: public-key credentials bound to a specific origin eliminate phishing, credential stuffing, and password reuse in one stroke. But the long tail of legacy authentication — password reset flows, OAuth implementations, SAML assertion handling, and MFA bypass paths — continues to produce critical findings across bug bounty programs.

This page collects research, writeups, tools, and standards covering authentication attacks and defenses: OAuth and SAML vulnerabilities, MFA bypass techniques, passkey rollouts, session management, and the OWASP cheat sheets that codify what good authentication looks like.

From OWASP Authentication Cheat Sheet

Read the AuthN guideA long-form, source-cited deep dive synthesized from every resource below.
Date Added Link Excerpt
2026-06-28 NEW 2026Exploiting insecure cookie policies beginner 7 min readLibrary detailing the exploitation of insecure cookie policies, including Cross-Site Request Forgery (CSRF) due to missing SameSite or Secure flags, XSS cookie stealing when HttpOnly is absent, and cookie theft over insecure HTTP when the Secure flag is missing. The resource explains how these vulnerabilities can lead to session hijacking and account takeover by exploiting misconfigurations in cookie attributes. → intigriti.com
2026-06-23 NEW 2026Authentication bypass vulnerabilities in TeamCity: everything you need to know news 3 min readWriteup detailing CVE-2024-27198 and CVE-2024-27199, critical authentication bypass vulnerabilities in JetBrains TeamCity On-Premises versions prior to 2023.11.4. These flaws allow unauthenticated attackers to gain administrative control by manipulating URLs to access authenticated endpoints, enabling actions like creating new administrator accounts. CVE-2024-27199 also leverages path traversal to modify system settings and leak sensitive information. A security patch plugin is available as a workaround for those unable to immediately update. → wiz.io
2026-06-22 2026Exploiting Auth0 Defaults in XSS Attacks - elttam intermediate 8 min read XSSWriteup detailing how XSS vulnerabilities in applications using Auth0 can be exploited. It highlights that the default configuration of the insecure implicit grant flow in Auth0 applications, when combined with an API that allows all applications within a tenant access, enables attackers to steal access tokens. This allows pivoting to other systems, such as an administrative application, by chaining these misconfigurations.
2026-06-22 2026Secure password hashing in Go intermediate 9 min readLibrary for secure password hashing in Go, detailing best practices like salting and the importance of robust hashing algorithms such as Argon2id. It covers password storage concepts, explains attack methods like rainbow tables and brute-force, and provides insights into implementing Argon2id with specific parameters for memory, iterations, and parallelism, emphasizing the need to balance security with performance. → snyk.io
2026-06-22 2026Top 3 security best practices for handling JWTs intermediate 8 min read JWTGuide on securing JSON Web Tokens (JWTs) detailing three core best practices. It emphasizes keeping JWTs secret through HTTPS, HttpOnly/Secure cookie flags, and secure browser storage, while highlighting the risks of XSS. The guide stresses the importance of robust JWT validation, including signature verification, and checking claims like expiration, issuer, and audience. It also advocates for setting expiration times on JWTs to limit their usability and prevent unauthorized access. The article mentions tools like Snyk for identifying vulnerabilities and libraries such as Flask-JWT-Extended and PyJWT for implementation. → snyk.io
2026-06-22 2026Common SAML vulnerabilities and how to remediate them beginner 4 min readReference detailing common SAML vulnerabilities and their remediation, including signature validation to prevent XML tampering and XML signature wrapping, weak encryption of assertions, and message expiration using "NotBefore" and "NotOnOrAfter" to prevent replay attacks. It also addresses open redirect vulnerabilities exploitable via the "RelayState" parameter and suggests ensuring its value is a trusted URL before redirection, referencing `samlify` and `python3-saml` libraries. → snyk.io
2026-06-20 2026Emerging phishing campaign targeting AWS accounts news 4 min readWriteup on an emerging phishing campaign targeting AWS accounts, detailing its use of redirect chains via services like squarespace.com and cli.re to reach credential harvesting pages, often visually cloning the legitimate AWS sign-in page. The campaign leverages Amazon SES and CloudFront, with observed attacker-controlled domains including consoleportal[.]tech. It emphasizes securing AWS environments by disabling root logins via SCP, using FIDO security keys for MFA, enforcing SSO, implementing least privilege, and enabling Amazon CloudTrail for logging and impact assessment. → wiz.io
2026-06-20 2026AWS Console Session Traceability: How Attackers Obfuscate Identity Through the AWS Console intermediate 8 min readWriteup on the "Console Conceal" technique, which attackers can use to obfuscate their identity within AWS by manipulating role session names and exploiting a quirk in how AWS Console actions are logged in CloudTrail. This method bypasses standard traceability, making it difficult to attribute actions back to compromised credentials, especially when SourceIdentity is not configured. The analysis details how attackers can assume roles with misleading session names and how security teams can still investigate by correlating actions with the original AssumeRole events. → wiz.io
2026-06-20 2026“Bug Bounty Bootcamp #48: OAuth + XSS ” intermediate Bug Bounty XSSThis Bug Bounty Bootcamp #48 focuses on a potent combination for account takeover: OAuth vulnerabilities and Cross-Site Scripting (XSS). The article, "The Ultimate Account Takeover One-Two Punch," explores how these two attack vectors can be exploited in tandem to gain unauthorized access to user accounts. The content is hosted on InfoSec Write-ups and details the methods and techniques used in such exploits. No specific bounty payout amount is mentioned. → infosecwriteups.com
2026-06-19 2026“Bug Bounty Bootcamp #46: Not Allowed From Your IP?” advancedThis article from InfoSec Write-ups, "Bug Bounty Bootcamp #46: Not Allowed From Your IP?", details advanced techniques for bypassing authentication barriers in bug bounty hunting. The methods discussed include IP spoofing, brute-force attacks, and mass assignment, all aimed at gaining unauthorized access. The focus is on exploiting authentication vulnerabilities to overcome access restrictions. No specific bug bounty payout amount is mentioned in the provided text. → infosecwriteups.com
2026-06-18 2026The many ways to obtain credentials in AWS beginner 5 min read SecretsLibrary detailing numerous methods for attackers to obtain AWS credentials, beyond the typical IMDSv2 requests to 169.254.169.254. It covers AWS SDK credential providers, IAM user access keys, environment variables in Lambda, EC2 user-data, credential files, IMDSv1 and IMDSv2, container services like ECS and EKS (including EKS Pod Identities, IRSA), Default Host Management Configuration (DHMC), Systems Manager hybrid activation, AWS IoT's iot:AssumeRoleWithCertificate, IAM Roles Anywhere, Cognito's GetCredentialsForIdentity, and DataSync's certificate-based authentication. → wiz.io
2026-06-18 2026Avoiding mistakes with AWS OIDC integration conditions intermediate 6 min readLibrary documenting mistakes in AWS OIDC integration conditions, highlighting issues with GitHub Actions, Terraform Cloud, Microsoft Defender, and GitLab. It emphasizes the importance of specific IAM trust policy conditions like "sub" and "sts:RoleSessionName" to prevent unauthorized access, detailing variations across over twenty vendors and built-in AWS identity providers, and advises ensuring both "aud" and "sub" conditions when available. → wiz.io
2026-06-17 202627 Years in the Dark: OpenBSD Fixes Ancient Remote Kernel Auth Bypass news 3 min readLibrary for OpenBSD's sppp(4) subsystem that addresses a 27-year-old remote kernel authentication bypass vulnerability (CVE-2026-55706) in the Password Authentication Protocol (PAP). The bug allowed unauthenticated access by exploiting how length fields were handled in `bcmp` calls, leading to both authentication bypass and kernel heap over-reads. The fix introduces an exact-length pre-check for credentials, mirroring the CHAP handler, ensuring proper validation.
2026-06-17 2026Bug Bounty Bootcamp #45: Token? intermediate API SecThis Bug Bounty Bootcamp #45 focuses on a vulnerability where a password reset mechanism leaks a "magic token" in the API response. The content also mentions an even more problematic endpoint that provides this token directly. The article's title suggests this is a critical finding relevant to bug bounty hunting. → infosecwriteups.com
2026-06-15 2026When a Government Pulls an AI Model: What the Fable 5 and Mythos 5 Suspension Means for Security Teams news 10 min read AIAnalysis of the suspension of Anthropic's Fable 5 and Mythos 5 models highlights security lessons regarding AI dependencies and dual-use capabilities. The shutdown, triggered by a reported AI jailbreak involving code analysis and remediation, mirrors familiar challenges in application security where tools like SAST engines and fuzzers are inherently dual-use. The event underscores the importance of defense-in-depth, risk-based prioritization, and coordinated disclosure, practices the security field has developed to manage powerful technologies that could be misused. → snyk.io
2026-06-14 2026From Compromised Keys to Phishing Campaigns: Inside a Cloud Email Service Takeover intermediate 7 min read SecretsLibrary detailing a cloud email service takeover campaign that leveraged compromised AWS access keys. Attackers bypassed Amazon SES sandbox restrictions by using a novel, multi-regional `PutAccountDetails` request to gain production mode access, subsequently verifying attacker-owned and weakly protected legitimate domains to launch phishing operations targeting tax forms. The campaign utilized a commercial traffic analysis service for redirection to evade detection and facilitate credential theft, highlighting the risks of SES abuse including reputational damage and potential for broader compromise. → wiz.io
2026-06-13 2026Major AI Clients Shipping With Broken OAuth Implementations (JUNE 2026 UPDATE) news 4 min read API SecReference detailing OAuth refresh token implementation issues in major AI clients like Cursor, Claude, and VS Code, as per the MCP authorization specification and SEP-2207. It highlights failures in metadata discovery for Claude Code and incomplete support across clients, noting the workaround solution provided by the `mcp-remote` tool.
2026-06-13 2026I Simulated an SSH Brute-Force Attack on My Ubuntu Server — Here’s How Fail2Ban Stopped It intermediateThe author details setting up an attack lab to simulate SSH brute-force attempts against their Ubuntu server. The primary focus is on observing how Fail2Ban functions to detect and automatically block repeated failed login sequences. The article aims to provide a practical understanding of Fail2Ban's effectiveness in protecting against such attacks. No bug bounty payout amount is mentioned. → infosecwriteups.com
2026-06-13 2026Beyond the Patch: Understanding the SonicWall SSL-VPN MFA Bypass Exposure newsA SonicWall SSL-VPN vulnerability, CVE-2024–12802, allows attackers to bypass Multi-Factor Authentication (MFA). The flaw lies in how SSL-VPN handles UPN and SAM account formats separately. Attackers can exploit alternative login formats to circumvent MFA, even when it seems active. This issue affects SonicWall Gen6 SSL-VPN devices and has been linked to ransomware attacks. The content does not state a specific bug bounty payout amount. → infosecwriteups.com
2026-06-12 2026Marking Your Own Homework (Check Point Remote Access VPN IKEv1 Authentication Bypass CVE-2026-50751) - watchTowr Labs news 11 min read RCEWriteup of CVE-2026-50751, a Check Point Remote Access VPN authentication bypass, details a logic flaw in IKEv1 certificate validation. The vulnerability, present in various Gaia versions, allowed attackers to bypass signature verification by manipulating a `process_machine_certs` parameter and a `peer_flags` bit, preventing the gateway from properly authenticating clients. Exploited in the wild by threat actors including Qilin ransomware affiliates, the issue was patched by Check Point in subsequent hotfixes. → labs.watchtowr.com
2026-06-12 20263 OAuth TTPs Seen This Month — and How to Detect Them with Entra ID Logs intermediate 10 min read JWTLibrary for detecting OAuth TTPs in Azure environments. It details device code phishing, where attackers exploit the device code flow to trick victims into authenticating with MFA, granting the attacker a token. It also covers Resource Owner Password Credentials (ROPC) abuse, leveraging legacy flows without MFA or browser consent for credential stuffing and persistence, often targeting applications like Azure AD PowerShell. Finally, it explains how attackers can use specific token-resource combinations, such as Microsoft Authentication Broker and Intune Enrollment, to register a device and bypass Conditional Access policies. KQL queries are provided for log analysis. → wiz.io
2026-06-11 2026Authentication issues related to API requests beginner API SecThis content highlights authentication problems that can occur with API requests. These issues can compromise the security and integrity of data transmitted through APIs. Without proper authentication, unauthorized users could potentially access sensitive information or perform actions they are not permitted to do. The focus is on identifying and addressing these vulnerabilities to ensure secure API communication. No specific bounty payout amount is mentioned.
2026-06-11 2026Would You Click ‘Accept’? Automatically detecting malicious Azure OAuth applications using LLMs intermediate 11 min read AILibrary for detecting malicious Azure OAuth applications by analyzing campaigns, identifying homoglyph attacks, and flagging deviations from legitimate integrations like publisher verification status, homepage URLs, and owning tenant domains. This tool helps identify stealthy threats that blend with legitimate business integrations, preventing unauthorized access and privilege escalation. → wiz.io
2026-06-11 202610 year old critical vulnerability in phpBB affecting tens of millions of users across thousands of forums news 2 min read RCETool for discovering critical Authentication Bypass vulnerabilities in phpBB. Aikido Attack identified a flaw affecting versions up to 3.3.16 and 4.0.0-a2, allowing unauthenticated users to gain valid sessions and impersonate any user, including administrators. This vulnerability, reported via HackerOne, led to a swift patch in phpBB version 3.3.17. → aikido.dev
2026-06-11 2026You Can't Secure What You Can't See: Making Non-Human Identities Governable beginner 4 min read SecretsLibrary for governing non-human identities (NHIs), it provides a centralized, searchable view of NHIs across infrastructure, surfacing origin, path, environment, risk level, and ownership status. This enables continuous governance by allowing teams to review changes, spot drift early, and prioritize remediation. It identifies risky patterns such as public leaks, cross-environment secrets, reused credentials, long-lived secrets, and overprivileged identities, offering context through an exploration map to understand dependencies before taking action like revoking or rotating credentials. → blog.gitguardian.com
2026-06-10 2026Volkswagen blocks Home Assistant by requiring client assertion news 1 min readLibrary issue detailing how Volkswagen blocked Home Assistant integration by requiring client assertion. The issue stems from Volkswagen's identity provider at `identity.vwgroup.io/oidc/v1/authorize`, which now rejects requests with `response_type=code token id_token`, preventing the library from obtaining necessary access tokens. This blocks login functionality for users.
2026-06-10 2026ServiceNow's Virtual Agent Vulnerability Shows Why AI Security Needs Traditional AppSec Foundations beginner 6 min read AI AuthZLibrary for identifying and mitigating vulnerabilities in AI agents, such as the ServiceNow Virtual Agent exploit. This resource highlights that securing AI requires foundational application security practices, including threat modeling for agent behavior, Dynamic Application Security Testing (DAST) to detect hardcoded secrets and authorization flaws, and AI red teaming to uncover the impact of autonomous agent actions. It emphasizes a layered security approach, auditing agent permissions, enforcing strong API authentication, and implementing continuous testing. → snyk.io
2026-06-10 2026SQL Injection in Password Reset: Full Database, One Email intermediate SQLiA SQL injection vulnerability in a password reset feature granted a researcher full read access to the entire database. By manipulating a "ukey" parameter in the password reset link, the attacker could retrieve all user records, including plaintext password hashes. The vulnerability was reported in early 2025 and remained unpatched. The content does not specify a bug bounty payout amount. → infosecwriteups.com
2026-06-09 2026Context.ai OAuth Token Compromise news 4 min read Supply ChainAnalysis of the Context.ai OAuth token compromise details a supply chain attack vector where compromised tokens for a third-party AI tool allowed attackers access to Vercel's Google Workspace. This incident highlights the risks associated with broad OAuth permissions and trusted SaaS integrations, similar to prior attacks like the Salesloft Drift incident and the Midnight Blizzard campaign. The analysis provides guidance on revoking access, rotating credentials, and investigating account activity across Google Workspace, Azure AD, and Okta. → wiz.io
2026-06-08 2026Critical Buffer Overflow Vulnerability in PAN-OS Exploited in-the-Wild news 1 min read RCEAnalysis of CVE-2026-0300, a critical buffer overflow vulnerability in Palo Alto Networks PAN-OS, enabling unauthenticated attackers to achieve remote code execution with root privileges. The issue resides in the User-ID Authentication Portal (ports 6081/6082) and is actively exploited in limited cases, particularly when exposed externally. Exploitation risk is elevated for publicly accessible instances, with security teams advised to patch immediately, restrict access, or disable the portal if not required. → wiz.io
2026-06-08 2026Qinglong task scheduler RCE vulnerabilities exploited in the wild for cryptomining news 5 min read RCELibrary detailing two authentication bypass vulnerabilities in Qinglong task scheduler (versions 2.20.1 and earlier), including CVE-2026-3965 and CVE-2026-4047. These flaws enabled unauthenticated remote code execution, exploited for cryptomining campaigns. The analysis highlights common middleware misconfigurations and emphasizes treating self-hosted applications as attack surfaces, recommending audits, monitoring, and timely updates. → snyk.io
2026-06-08 2026Initial Access Changed, The Attack Path Did Not: Findings From The Verizon 2026 DBIR news 9 min read Secrets Supply ChainAnalysis of the Verizon 2026 DBIR highlights that while exploited vulnerabilities are the primary initial access vector, credential abuse remains central to breach progression. Attackers leverage leaked passwords, API keys, OAuth tokens, and other secrets found in code repositories, communication platforms, and CI/CD pipelines to expand their access. Third-party trust, exemplified by the Salesloft Drift and Salesforce breach, also presents significant risk through compromised integrations and delegated authorization. Ransomware frequently monetizes this valid access, with stolen credentials appearing in a significant percentage of breaches across various attack patterns. Incident response must prioritize credential exposure analysis, understanding what secrets unlock, their location, validity, ownership, and dependencies. → blog.gitguardian.com
2026-06-08 2026Detecting CVE-2026-0265 at Scale: PAN-OS CAS Authentication Bypass news 8 min read JWTTool for detecting CVE-2026-0265, a pre-authentication JWT signature bypass in PAN-OS and Panorama. The vulnerability, exploitable when Cloud Authentication Service (CAS) is attached to an authentication profile, affects both GlobalProtect portals and the management interface. This detection script utilizes a single anonymous HTTP request to the `/global-protect/prelogin.esp` endpoint to definitively determine a system's vulnerable or non-vulnerable status, by examining the presence of `<cas-auth>yes</cas-auth>` and extracting the authoritative PAN-OS version from an embedded JWT. → bishopfox.com
2026-04-29 20267 MCP Authentication Vulnerabilities B2B SaaS Vendors Must Prevent beginner 12 min readAnalysis of 281 MCP implementations by Pynt reveals significant authentication vulnerabilities in AI agent integrations. B2B SaaS vendors must address token leakage via tool results, confused deputy via token passthrough, prompt injection leading to auth bypass, and over-scoped OAuth grants. Prompt injection, exemplified by a Supabase Cursor incident, allows attackers to exploit untrusted external content as executable instructions. Mitigations include sanitizing tool results, independent authentication to downstream services, strict input validation, and enforcing least-privilege OAuth scopes, aligning with MCP spec updates like RFC 8707. → securityboulevard.com
2026-04-22 2026OAuth2 Proxy Authentication Bypass via X-Forwarded-Uri (CVE-2026-40575) news 2 min readWriteup of CVE-2026-40575 detailing a critical authentication bypass in OAuth2 Proxy. This vulnerability arises from trusting client-supplied `X-Forwarded-Uri` headers in reverse proxy configurations using `–skip_auth_routes` or `–skip-auth-regex`, allowing attackers to bypass authentication by spoofing this header. Mitigation involves upgrading to version 7.15.2 or later, configuring `–trusted-proxy-ip`, and stripping or overwriting the `X-Forwarded-Uri` header at the reverse proxy level. → dailycve.com
2026-04-22 2026Keycloak SAML Disabled Client SSO Bypass (CVE-2026-3047) news 2 min readWriteup of CVE-2026-3047, a CVSS 8.8 flaw in Keycloak's SAML broker (`org.keycloak.broker.saml`), enabling SSO bypass. Attackers can exploit this by initiating login through a SAML client that is simultaneously disabled and configured as an IdP-initiated broker landing target. Despite its disabled status, the broker incorrectly completes the authentication flow, granting unauthorized SSO access to enabled clients within the Keycloak realm. Exploitation requires no prior authentication, allowing remote attackers to bypass security restrictions. → thehackerwire.com
2026-04-22 2026CVE-2026-2092: Keycloak Auth Bypass Vulnerability news 4 min readWriteup of CVE-2026-2092, a Keycloak authentication bypass vulnerability, details how attackers can inject encrypted assertions into unsigned SAML responses. This flaw, affecting Keycloak and related Red Hat products, allows unauthorized access by substituting an attacker's valid signed assertion with one for an arbitrary principal, bypassing proper validation and potentially compromising identity federation. Mitigation involves applying patches and configuring SAML identity providers to always sign SAML responses in addition to assertions. → sentinelone.com
2026-04-22 2026CVE-2026-1529: Bypassing Keycloak Org Security news 4 min readWriteup of CVE-2026-1529, a critical bypass in Keycloak's Organizations feature, details how attackers can forge JWT invitation tokens by omitting signature verification. This vulnerability, with a CVSS score of 8.1, allows unauthorized access to restricted organizations by simply modifying the organization ID within a valid invite token. The report covers the exploit technique, the impact on multi-tenancy, and remediation steps including immediate updates to Keycloak versions 26.x or disabling the Organizations feature.
2026-04-22 2026OAUTHBEARER Bypass and Sensitive Logging Leaks Hit Apache Kafka news 2 min readVulnerability writeup detailing CVE-2026-33557, an OAUTHBEARER bypass in Apache Kafka where the DefaultJwtValidator accepts any JWT by failing to verify signatures, issuers, or audiences, allowing attackers to impersonate users. It also covers CVE-2026-33558, a moderate risk of sensitive data leaks through verbose DEBUG logging in the NetworkClient component. Affected versions include Kafka clients 0.11.0 through 3.9.1, and 4.0.0.
2026-04-22 2026CVE-2025-26788: Passkey Authentication Bypass in StrongKey FIDO Server news 3 min readWriteup of CVE-2025-26788, a passkey authentication bypass in StrongKey FIDO Server versions 4.10.0 through 4.15.0. This vulnerability allows account takeover by exploiting a flaw where the server fails to distinguish between discoverable and non-discoverable credential flows, enabling an attacker to use their own passkey with a victim's username. The writeup includes a proof-of-concept demonstrating the attack and recommends updating to StrongKey FIDO Server version 4.15.1.
2026-04-22 2026Analyzing the rise in device code phishing attacks in 2026 news 12 min readAnalysis of device code phishing attacks highlights a significant rise in this account takeover technique since 2026, exploiting the OAuth 2.0 Device Authorization Grant. Attackers leverage this flow, commonly used by CLI tools, to trick users into issuing access tokens to malicious applications, bypassing passwords, MFA, and passkeys. Prominent targets include Microsoft, Google, Salesforce, GitHub, and AWS. The "EvilTokens" PhaaS kit has been identified as a major driver of these campaigns, offering sophisticated anti-bot measures and user-friendly interfaces. Research has traced the evolution of these kits, noting advancements in hosting, code generation, and payload delivery methods.
2026-04-22 2026SAML rough quarter: Five critical vulnerabilities in four months news 9 min readLibrary of resources detailing critical SAML vulnerabilities, including CVE-2026-3055 in Citrix NetScaler, "The Fragile Lock" research by PortSwigger (CVE-2025-66568, CVE-2025-66567) revealing parser-level bypasses, CVE-2026-25922 in authentik for assertion injection, CVE-2026-34840 in OneUptime for auth bypass due to signature verification decoupling, and CVE-2026-20101 in Cisco Secure Firewall leading to DoS. These highlight systemic issues in SAML XML processing and signature validation.
2026-04-22 2026CVE-2024-9956: Critical WebAuthentication Vulnerability in Chrome on Android news 3 min readWriteup of CVE-2024-9956 details a critical flaw in Google Chrome on Android, allowing local attackers within Bluetooth range to steal PassKeys via crafted HTML pages. This vulnerability, impacting WebAuthn's FIDO:/ URI scheme handling, could lead to account takeovers across various browsers like Safari on iOS and Firefox on Android. The exploit involves tricking users into visiting malicious sites that silently trigger Bluetooth-based authentication requests, enabling attackers to intercept credentials and gain unauthorized access. Mitigation includes updating Chrome, disabling WebAuthn via Bluetooth, and exercising caution with links.
2026-04-22 2026CVE-2026-34457 Detail (OAuth2 Proxy) - NVD news 1 min readWriteup detailing CVE-2026-34457, an authentication bypass vulnerability in OAuth2 Proxy affecting versions prior to 7.15.2. This flaw occurs in specific configurations using auth_request-style integrations with either `--ping-user-agent` or `--gcp-healthchecks` enabled, allowing unauthenticated attackers to access protected resources by mimicking the health check User-Agent. The vulnerability is categorized under CWE-290: Authentication Bypass by Spoofing.
2026-04-19 2026Bypassing MFA with OAuth Abuse: Pentesting SSO Flows intermediate 4 min readLibrary for exploiting OAuth misconfigurations, focusing on bypassing Multi-Factor Authentication (MFA) in Single Sign-On (SSO) flows. It details techniques for token reuse, session fixation, open redirect vulnerabilities, and improper scope enforcement, guiding users through tools such as OAuth2 Proxy, mitmproxy, Evilginx, and OauthTester to identify and exploit these weaknesses.
2026-04-19 2026SSO Protocol Security: Critical Vulnerabilities in SAML, OAuth, OIDC, JWT (2025) advanced 24 min readLibrary cataloging SAML, OAuth, OIDC, and JWT vulnerabilities, including XML Signature Wrapping attacks affecting Ruby SAML (CVE-2024-45409) and GitHub Enterprise Server (CVE-2024-6800), XML canonicalization bugs in various libraries (CVE-2017-11427 to CVE-2017-11430, CVE-2018-0489), assertion replay issues (CVE-2018-14637), and vendor-specific flaws like Oracle Access Manager (CVE-2021-35587). The analysis highlights recurring authentication bypasses and token forgery risks, emphasizing the impact and exploitability of these critical SSO protocol weaknesses.
2026-04-19 2026The Art of Breaking OAuth: Real-World Exploits and Misuses intermediateThe Art of Breaking OAuth: Real-World Exploits and Misuses → infosecwriteups.com
2026-04-19 2026OAuth2-Proxy Authentication Bypass (CVE-2025-54576) news 3 min readWriteup detailing CVE-2025-54576, an authentication bypass vulnerability in OAuth2-Proxy versions 7.10.0 and below. The flaw lies in the `skip_auth_routes` configuration, where regex patterns intended for paths were incorrectly applied to the entire request URI, including query parameters. This allowed attackers to craft URLs with malicious query strings to bypass authentication. The fix, implemented in version 7.11.0, restricts pattern matching to only the request path. → zeropath.com
2026-04-19 2026OAuth SSO WordPress Plugin JWT Bypass (CVE-2025-9485) news 2 min readWriteup of CVE-2025-9485, a JWT bypass vulnerability in miniOrange's OAuth Single Sign On – SSO (OAuth Client) WordPress plugin. Versions up to and including 6.26.12 improperly verify JWT signatures, allowing attackers to forge tokens and gain administrator access by manipulating the `sub` claim. This flaw, classified as CWE-347, affects thousands of sites using the plugin for integration with providers like Azure AD and Google Workspace. → zeropath.com
2026-04-17 2026WebAuthn: Complete Guide to Passwordless, FIDO2, Passkeys (TerraZone) beginner 13 min readLibrary detailing WebAuthn, a W3C and FIDO Alliance standard, offers a robust approach to passwordless authentication using public-key cryptography. It explains the core concepts of registration and authentication ceremonies, including the JavaScript API calls involved, and highlights the security benefits derived from public-key cryptography, origin binding, and challenge-response mechanisms, rendering it inherently phishing-resistant. The guide also provides practical advice on integrating WebAuthn passkeys into dApps, contrasting it with traditional wallet-based authentication.

Frequently Asked Questions

What is the difference between authentication and authorization?
Authentication (authn) verifies who a user is — typically through passwords, tokens, certificates, or biometrics. Authorization (authz) determines what an authenticated user is allowed to do. The two are often conflated but rely on different mechanisms and fail in different ways. A correctly authenticated user can still be a victim of broken authorization, and vice versa.
What are the most common authentication vulnerabilities?
Common authentication flaws include credential stuffing, weak password policies, missing or bypassable multi-factor authentication, predictable session tokens, password reset poisoning, OAuth redirect_uri manipulation, SAML signature wrapping, and JWT algorithm confusion. Many real-world breaches start with authentication weaknesses rather than novel exploitation.
Are passkeys actually more secure than passwords?
Yes — passkeys use public-key cryptography bound to a specific origin, which eliminates phishing, credential stuffing, and password reuse attacks. The private key never leaves the user's device. Passkeys are based on the WebAuthn and FIDO2 standards and are now supported by major browsers, operating systems, and identity providers.

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