Authlib is a Python library which builds OAuth and OpenID Connect servers. Prior to 1.9.1, Authlib's OctKey.import_key() and HMAC signing and verification path accept zero-length key material. If an application's secret lookup can return an empty string or empty bytes, a remote attacker can compute the deterministic HS256, HS384, or HS512 signature for arbitrary token claims and have Authlib treat the token as authentic. This issue is fixed in version 1.9.1.
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Fixes
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References
History
Fri, 23 Oct 2026 03:45:00 +0000
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| First Time appeared |
Authlib
Authlib authlib |
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| Vendors & Products |
Authlib
Authlib authlib |
Fri, 23 Oct 2026 00:45:00 +0000
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| Description | Authlib is a Python library which builds OAuth and OpenID Connect servers. Prior to 1.9.1, Authlib's OctKey.import_key() and HMAC signing and verification path accept zero-length key material. If an application's secret lookup can return an empty string or empty bytes, a remote attacker can compute the deterministic HS256, HS384, or HS512 signature for arbitrary token claims and have Authlib treat the token as authentic. This issue is fixed in version 1.9.1. | |
| Title | Authlib accepts an empty HMAC key, allowing JWS/JWT signature forgery (HS256/HS384/HS512) | |
| Weaknesses | CWE-1391 CWE-287 CWE-326 |
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| References |
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| Metrics |
cvssV3_1
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Projects
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Status: PUBLISHED
Assigner: GitHub_M
Published:
Updated: 2026-10-22T21:14:03.060Z
Reserved: 2026-10-21T20:34:25.600Z
Link: CVE-2026-114616
No data.
Status : Received
Published: 2026-10-22T22:18:04.420
Modified: 2026-10-22T22:18:04.420
Link: CVE-2026-114616
No data.
OpenCVE Enrichment
Updated: 2026-10-23T03:30:15Z