CVE-2025-61152: python-jose thru · Improper Privilege Management
Source CVE Database V5
Not known to be exploited · CVSS 6.5 Medium.
Data as of 26 Oct 2026, 16:39 UTC
- EPSS
- 0.3% chance of exploitation in 30 days – higher than 25% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:NExploitation evidence
Disclosed: evidence found.
CVE published 10 Oct 2025
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.
What to do
AI-suggested
- Immediately audit all applications using python-jose for JWT validation to determine if they accept tokens with 'alg=none' or disable signature verification.
- Ensure that the application explicitly rejects JWT tokens with 'alg=none' by configuring the library or implementing custom validation logic.
- Avoid setting 'verify_signature' to false; signature verification must always be enabled in production environments.
- Update to a patched version of python-jose once available or apply community patches that enforce rejection of 'alg=none' tokens.
- Implement additional layers of authentication and authorization checks beyond JWT claims to reduce reliance on token integrity alone.
- Monitor logs for suspicious authentication attempts involving tokens with 'alg=none' or unusual claims.
- Educate developers about secure JWT handling practices, emphasizing the risks of accepting unsigned tokens.
- Consider using alternative JWT libraries that enforce stricter validation policies if python-jose cannot be updated promptly.
- Conduct penetration testing focused on JWT authentication to identify potential exploitation paths.
- Maintain an incident response plan to quickly address any detected misuse of forged tokens.
Description
python-jose thru 3.3.0 allows JWT tokens with 'alg=none' to be decoded and accepted without any cryptographic signature verification. A malicious actor can craft a forged token with arbitrary claims (e.g., is_admin=true) and bypass authentication checks, leading to privilege escalation or unauthorized access in applications that rely on python-jose for token validation. This issue is exploitable unless developers explicitly reject 'alg=none' tokens, which is not enforced by the library. NOTE: all parties agree that the issue is not relevant because it only occurs in a "verify_signature": False situation.