Bug 2559395 (CVE-2026-114616) - CVE-2026-114616 authlib: authlib: Authentication bypass via zero-length HMAC key
Summary: CVE-2026-114616 authlib: authlib: Authentication bypass via zero-length HMAC key
Keywords:
Status: NEW
Alias: CVE-2026-114616
Product: Security Response
Classification: Other
Component: vulnerability
Version: unspecified
Hardware: All
OS: Linux
high
high
Target Milestone: ---
Assignee: Product Security DevOps Team
QA Contact:
URL:
Whiteboard:
Depends On: 2560032 2560033 2560034 2560035 2560037
Blocks:
TreeView+ depends on / blocked
 
Reported: 2026-10-22 21:34 UTC by OSIDB Bzimport
Modified: 2026-10-23 16:57 UTC (History)
46 users (show)

Fixed In Version:
Clone Of:
Environment:
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Description OSIDB Bzimport 2026-10-22 21:34:25 UTC 
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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