PYSEC-2026-2118

Vulnerability from pysec - Published: 2026-03-06 07:16 - Updated: 2026-07-13 05:48
VLAI
Details

Authlib is a Python library which builds OAuth and OpenID Connect servers. From version 1.6.5 to before version 1.6.7, previous tests involving passing a malicious JWT containing alg: none and an empty signature was passing the signature verification step without any changes to the application code when a failure was expected.. This issue has been patched in version 1.6.7.

Severity
9.8 (Critical)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Impacted products
Name purl
authlib pkg:pypi/authlib
Aliases
To clipboard 

{
  "affected": [
    {
      "ecosystem_specific": {},
      "package": {
        "ecosystem": "PyPI",
        "name": "authlib",
        "purl": "pkg:pypi/authlib"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "1.6.5"
            },
            {
              "fixed": "1.6.7"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1.6.5",
        "1.6.6"
      ]
    }
  ],
  "aliases": [
    "CVE-2026-28802",
    "GHSA-7wc2-qxgw-g8gg"
  ],
  "details": "Authlib is a Python library which builds OAuth and OpenID Connect servers. From version 1.6.5 to before version 1.6.7, previous tests involving passing a malicious JWT containing alg: none and an empty signature was passing the signature verification step without any changes to the application code when a failure was expected.. This issue has been patched in version 1.6.7.",
  "id": "PYSEC-2026-2118",
  "modified": "2026-07-13T05:48:01.549716Z",
  "published": "2026-03-06T07:16:01.053Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://access.redhat.com/security/cve/CVE-2026-28802"
    },
    {
      "type": "WEB",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-28802.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://access.redhat.com/errata/RHSA-2026:19375"
    },
    {
      "type": "ADVISORY",
      "url": "https://access.redhat.com/errata/RHSA-2026:4942"
    },
    {
      "type": "ADVISORY",
      "url": "https://access.redhat.com/errata/RHSA-2026:5168"
    },
    {
      "type": "ADVISORY",
      "url": "https://access.redhat.com/errata/RHSA-2026:5665"
    },
    {
      "type": "ADVISORY",
      "url": "https://access.redhat.com/errata/RHSA-2026:6309"
    },
    {
      "type": "ADVISORY",
      "url": "https://access.redhat.com/errata/RHSA-2026:6568"
    },
    {
      "type": "REPORT",
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2445120"
    },
    {
      "type": "FIX",
      "url": "https://github.com/authlib/authlib/commit/a61c2acb807496e67f32051b5f1b1d5ccf8f0a75"
    },
    {
      "type": "FIX",
      "url": "https://github.com/authlib/authlib/commit/b87c32ed07b8ae7f805873e1c9cafd1016761df7"
    },
    {
      "type": "EVIDENCE",
      "url": "https://github.com/authlib/authlib/security/advisories/GHSA-7wc2-qxgw-g8gg"
    }
  ],
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ]
}



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