Bug 2546040

Summary: CVE-2026-85394 python-josepy: python-jose through 3.5.0 Algorithm Confusion via DER-encoded Public Key as HMAC Secret [epel-all]
Product: [Fedora] Fedora EPEL Reporter: aedmond
Component: python-josepyAssignee: Fedora Certbot SIG <certbot-sig>
Status: NEW --- QA Contact: Fedora Extras Quality Assurance <extras-qa>
Severity: high Docs Contact:
Priority: high    
Version: epel10CC: certbot-sig, nb, turboben
Target Milestone: ---Keywords: Security, SecurityTracking
Target Release: ---   
Hardware: Unspecified   
OS: Unspecified   
Whiteboard: {"flaws": ["4d56151c-5976-4fe2-942e-1febb3a26c51"]}
Fixed In Version: Doc Type: ---
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Documentation: --- CRM:
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Embargoed:
Bug Depends On:    
Bug Blocks: 2528187    

Description aedmond 2026-10-05 18:31:03 UTC 
Disclaimer: Community trackers are created by Red Hat Product Security team on a best effort basis. Package maintainers are required to ascertain if the flaw indeed affects their package, before starting the update process.

python-jose through 3.5.0 fails to properly validate asymmetric keys in HMAC initialization, accepting DER-encoded public keys that lack PEM armor or SSH prefixes. Attackers holding the service's public key can forge HS256 tokens that pass verification when algorithms are not explicitly restricted. This is an incomplete fix for CVE-2024-33663.