{"cve":"CVE-2026-28490","nvd":{"published":"2026-03-16T18:16:07.557","modified":"2026-06-17T10:28:44.203","status":"Analyzed","description":"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.","cvss_v4":{"vector":"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","score":8.3},"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:L/A:N","score":6.5},"cwes":["CWE-203","CWE-327"],"references":["https://github.com/authlib/authlib/commit/48b345f29f6c459f11c6a40162b6c0b742ef2e22","https://github.com/authlib/authlib/releases/tag/v1.6.9","https://github.com/authlib/authlib/security/advisories/GHSA-7432-952r-cw78"],"products":["authlib:authlib"],"source":"nvd","synced_at":"2026-10-19T22:26:19.218427112+00:00"},"epss":{"cve":"CVE-2026-28490","score":0.00144,"percentile":0.0368,"date":"2026-10-31"},"kev":null,"osv":[{"id":"GHSA-7432-952r-cw78","url":"https://osv.dev/vulnerability/GHSA-7432-952r-cw78","summary":"Authlib Vulnerable to JWE RSA1_5 Bleichenbacher Padding Oracle","modified":"2026-07-13T07:26:14.887077371Z","packages":[{"ecosystem":"PyPI","name":"authlib","purl":"pkg:pypi/authlib","ranges":["<1.6.9"],"fixed":["1.6.9"]}]},{"id":"PYSEC-2026-2116","url":"https://osv.dev/vulnerability/PYSEC-2026-2116","summary":"","modified":"2026-07-13T07:15:14.229863781Z","packages":[{"ecosystem":"PyPI","name":"authlib","purl":"pkg:pypi/authlib","ranges":["<1.6.9"],"fixed":["1.6.9"]}]}],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}