id: PYSEC-2026-2119
published: "2026-06-22T21:16:24.017Z"
modified: "2026-07-13T05:48:01.609940Z"
aliases:
- CVE-2026-41479
- GHSA-w8p2-r796-3vmq
details: Authlib is a Python library which builds OAuth and OpenID Connect servers. Prior to 1.6.10 and 1.7.1, Authlib's OAuth 2.0 authorization endpoint can be turned into an unauthenticated open redirect when a request uses an unsupported response_type and supplies an attacker-controlled redirect_uri. The vulnerable behavior happens before client lookup and before any redirect URI validation. As a result, an attacker does not need a valid client registration, an authenticated user, or any prior state. A single request to the authorization endpoint is enough to obtain a 302 Location response to an arbitrary attacker-controlled URL. This vulnerability is fixed in 1.6.10 and 1.7.1.
affected:
- package:
    name: authlib
    ecosystem: PyPI
    purl: pkg:pypi/authlib
  ranges:
  - type: ECOSYSTEM
    events:
    - introduced: "0"
    - fixed: 1.6.10
  versions:
  - "0.1"
  - "0.10"
  - "0.11"
  - "0.12"
  - 0.12.1
  - "0.13"
  - "0.14"
  - 0.14.1
  - 0.14.2
  - 0.14.3
  - "0.15"
  - 0.15.1
  - 0.15.2
  - 0.15.3
  - 0.15.4
  - 0.15.5
  - 0.15.6
  - 0.1rc0
  - "0.2"
  - 0.2.1
  - "0.3"
  - "0.4"
  - 0.4.1
  - "0.5"
  - 0.5.1
  - "0.6"
  - "0.7"
  - "0.8"
  - "0.9"
  - 1.0.0
  - 1.0.0a1
  - 1.0.0a2
  - 1.0.0b1
  - 1.0.0b2
  - 1.0.0rc1
  - 1.0.1
  - 1.1.0
  - 1.2.0
  - 1.2.1
  - 1.3.0
  - 1.3.1
  - 1.3.2
  - 1.4.0
  - 1.4.1
  - 1.5.0
  - 1.5.1
  - 1.5.2
  - 1.6.0
  - 1.6.1
  - 1.6.2
  - 1.6.3
  - 1.6.4
  - 1.6.5
  - 1.6.6
  - 1.6.7
  - 1.6.8
  - 1.6.9
  ecosystem_specific: {}
references:
- type: FIX
  url: https://github.com/authlib/authlib/commit/3be08468201a7766a93012ce149ea12822cab096
- type: EVIDENCE
  url: https://github.com/authlib/authlib/security/advisories/GHSA-w8p2-r796-3vmq
severity:
- type: CVSS_V3
  score: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N