CVE-2025-14546
Versions of the package fastapi-sso before 0.19.0 are vulnerable to Cross-site Request Forgery (CSRF) due to the improper validation of the OAuth state parameter during the authentication callback. While the get_login_url method allows for state generation, it does not persist the state or bind it to the user's session. Consequently, the verify_and_process method accepts the state received in the query parameters without verifying it against a trusted local value. This allows a remote attacker to trick a victim into visiting a malicious callback URL, which can result in the attacker's account being linked to the victim's internal account.
EPSS 0.36% · 28.3th percentile
Risk Scores
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| PyPI | fastapi-sso | 0 |
| n/a | fastapi-sso | 0 |
Timeline
- Dec 19, 2025 CVE Published
- Dec 19, 2025 EPSS Score
- Dec 19, 2025 PoC Published
- Dec 24, 2025 EPSS Score
- Dec 28, 2025 EPSS Score
- Jan 2, 2026 EPSS Score
- Jan 6, 2026 EPSS Score
- Jan 11, 2026 EPSS Score
- Jan 16, 2026 EPSS Score
- Jan 20, 2026 EPSS Score
- Jan 25, 2026 EPSS Score
- Jan 30, 2026 EPSS Score
References
- https://github.com/tomasvotava/fastapi-sso/commit/6117d1a5ad498ba57d671e8a059ebe20db5abe02 fix
- https://github.com/tomasvotava/fastapi-sso/issues/266 discussion
- https://nvd.nist.gov/vuln/detail/CVE-2025-14546 advisory
- https://security.snyk.io/vuln/SNYK-PYTHON-FASTAPISSO-14386403 url
- https://github.com/tomasvotava/fastapi-sso package