CVE-2026-28802
March 06, 2026
Authlib is a Python library which builds OAuth and OpenID Connect servers. From version 1.6.5 to before version 1.6.7, previous tests involving passing a malicious JWT containing alg: none and an empty signature was passing the signature verification step without any changes to the application code when a failure was expected.. This issue has been patched in version 1.6.7.
Affected Packages
authlib (CONDA):
Affected version(s) >=0.10 <1.6.7Fix Suggestion:
Update to version 1.6.7https://github.com/authlib/authlib.git (GITHUB):
Affected version(s) >=v0.1 <v1.6.7Fix Suggestion:
Update to version v1.6.7authlib (PYTHON):
Affected version(s) >=1.6.5 <1.6.7Fix Suggestion:
Update to version 1.6.7Related Resources (5)
Do you need more information?
Contact UsCVSS v4
Base Score:
7.7
Attack Vector
NETWORK
Attack Complexity
LOW
Attack Requirements
NONE
Privileges Required
NONE
User Interaction
NONE
Vulnerable System Confidentiality
NONE
Vulnerable System Integrity
HIGH
Vulnerable System Availability
NONE
Subsequent System Confidentiality
NONE
Subsequent System Integrity
NONE
Subsequent System Availability
NONE
Exploit Maturity
POC
CVSS v3
Base Score:
7.5
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
HIGH
Availability
NONE
Weakness Type (CWE)
Improper Verification of Cryptographic Signature
EPSS
Base Score:
0.03
