CVE-2026-28490 (GCVE-0-2026-28490)

Vulnerability from cvelistv5 – Published: 2026-03-16 17:37 – Updated: 2026-03-16 18:17
VLAI
Title
Authlib Vulnerable to JWE RSA1_5 Bleichenbacher Padding Oracle
Summary
Authlib is a Python library which builds OAuth and OpenID Connect servers. Prior to version 1.6.9, a cryptographic padding oracle vulnerability was identified in the Authlib Python library concerning the implementation of the JSON Web Encryption (JWE) RSA1_5 key management algorithm. Authlib registers RSA1_5 in its default algorithm registry without requiring explicit opt-in, and actively destroys the constant-time Bleichenbacher mitigation that the underlying cryptography library implements correctly. This issue has been patched in version 1.6.9.
Severity
8.3 (High)
CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:H/VI:L/VA:N/SC:N/SI:N/SA:N
SSVC
Exploitation: poc Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-03-16 18:17 UTC
CWE
  • CWE-203 - Observable Discrepancy
  • CWE-327 - Use of a Broken or Risky Cryptographic Algorithm
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 7763 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
authlib authlib Affected: < 1.6.9
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

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