CVE-2026-28802NVD

Vulnerability Summary

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.

Severity Level

HIGH(7.7)

Published Date

Mar 6, 2026

Last Modified

Mar 6, 2026

Exploitation Status

No confirmed exploitation yet

EPSS Score (30-Day)

0.02%Probability

Root Weakness (CWE)

CWE-347: Unknown/Unlisted Weakness ↗

Refer to the official MITRE database for detailed architectural specifications regarding this weakness.

CVSS v4.0 Base Metrics — Score 7.7 (HIGH)

Attack VectorNetwork

Attack ComplexityLow

Attack RequirementsNone

Privileges RequiredNone

User InteractionNone

Confidentiality (Vulnerable System)None

Integrity (Vulnerable System)High

Availability (Vulnerable System)None

Confidentiality (Subsequent System)None

Integrity (Subsequent System)None

Availability (Subsequent System)None

Affected & Patched Versions

Affected Versions

Not provided by NVD for this CVE.

Patched Versions

Not provided by NVD for this CVE.

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