Description
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.
References (3)
Scores
CVSS v3
9.8
EPSS
0.0002
EPSS Percentile
4.8%
Attack Vector
NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CISA SSVC
Vulnrichment
Exploitation
none
Automatable
yes
Technical Impact
partial
Details
CWE
CWE-347
Status
published
Products (2)
authlib/authlib
1.6.5 - 1.6.7
pypi/authlib
1.6.5 - 1.6.7PyPI
Published
Mar 06, 2026
Tracked Since
Mar 06, 2026