CVE-2026-33544

HIGH

7.7

Description

Tinyauth is an authentication and authorization server. Prior to version 5.0.5, all three OAuth service implementations (GenericOAuthService, GithubOAuthService, GoogleOAuthService) store PKCE verifiers and access tokens as mutable struct fields on singleton instances shared across all concurrent requests. When two users initiate OAuth login for the same provider concurrently, a race condition between VerifyCode() and Userinfo() causes one user to receive a session with the other user's identity. This issue has been patched in version 5.0.5.

CVE Details

CVSS v3.1 Score7.7

SeverityHIGH

CVSS VectorCVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:C/C:H/I:H/A:N

Attack VectorNETWORK

ComplexityHIGH

Privileges RequiredLOW

User InteractionREQUIRED

Published4/2/2026

Last Modified4/3/2026

Sourcenvd

Honeypot Sightings0

Weaknesses (CWE)

CWE-362

References

https://github.com/steveiliop56/tinyauth/commit/f26c2171610d5c2dfbba2edb6ccd39490e349803(security-advisories@github.com)

https://github.com/steveiliop56/tinyauth/releases/tag/v5.0.5(security-advisories@github.com)

https://github.com/steveiliop56/tinyauth/security/advisories/GHSA-9q5m-jfc4-wc92(security-advisories@github.com)

IOC Correlations

No correlations recorded

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