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.
History

Fri, 10 Oct 2025 15:15:00 +0000

Type Values Removed Values Added
Weaknesses CWE-269
Metrics cvssV3_1

{'score': 6.5, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N'}

ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'poc', 'Technical Impact': 'partial'}, 'version': '2.0.3'}


Fri, 10 Oct 2025 14:00:00 +0000

Type Values Removed Values Added
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.
References

cve-icon MITRE

Status: PUBLISHED

Assigner: mitre

Published: 2025-10-10T00:00:00.000Z

Updated: 2025-10-10T14:22:45.776Z

Reserved: 2025-09-26T00:00:00.000Z

Link: CVE-2025-61152

cve-icon Vulnrichment

Updated: 2025-10-10T14:22:35.748Z

cve-icon NVD

Status : Received

Published: 2025-10-10T14:15:43.360

Modified: 2025-10-10T15:16:05.900

Link: CVE-2025-61152

cve-icon Redhat

No data.