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CVE-2026-114614VulnerabilityPublished Updated

Python authlib: From 0.13 until 1.8.0, authlib.common.security.is_secure_transport() uses a textual prefix comparison

Affects python-authlibSource GCVE Database

0
Authoritative record:CVE-2026-114614· Low 2.6

Not known to be exploited · CVSS 2.6 Low · fixed in 1.8.0 : update python-authlib when convenient.

Data as of 28 Oct 2026, 22:31 UTC

CVSS 3.1 base score
2.6Low
How severe the flaw is on the 0–10 CVSS scale.
Patch
Available – fixed in 1.8.0
CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:U/C:L/I:N/A:N

Exploitation evidence

  1. Disclosed: evidence found.

    CVE published 22 Oct 2026

  2. Detectable: no evidence on record.

    No public nuclei template indexed

  3. Weaponised: no evidence on record.

    No public exploit code indexed in Metasploit or Exploit-DB

  4. Exploited in the wild: no evidence on record.

    Not in CISA KEV and no source reports exploitation

  5. Observed by OffSeq Mirage: no evidence on record.

    No attack traffic recorded by OffSeq Mirage sensors

A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.

What to do

Affected software

ProductAffectedFixed in
Ubuntu 26.10python-authlibpkg:deb/ubuntu/python-authlib?arch=source&distro=stonkingOther threatsAffected
  • =1.6.7-1
  • =1.7.2-1
  • =1.7.2-2
Fixed in–
Ubuntu Pro 26.04 LTSpython-authlibpkg:deb/ubuntu/python-authlib?arch=source&distro=esm-apps/resoluteOther threatsAffected
  • 1.6.0-1 – 1.6.7-1ubuntu0.1~esm1
5 affected builds
Fixed in–
Ubuntu Pro 24.04 LTSpython-authlibpkg:deb/ubuntu/python-authlib?arch=source&distro=esm-apps/nobleOther threatsAffected
  • 1.2.1-1 – 1.3.0-1ubuntu0.1~esm2
4 affected builds
Fixed in–
Ubuntu Pro 22.04 LTSpython-authlibpkg:deb/ubuntu/python-authlib?arch=source&distro=esm-apps/jammyOther threatsAffected
  • 0.15.4-1 – 0.15.5-1ubuntu0.1~esm2
4 affected builds
Fixed in–

Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.

Description

Authlib is a Python library which builds OAuth and OpenID Connect servers. From 0.13 until 1.8.0, authlib.common.security.is_secure_transport() uses a textual prefix comparison for loopback HTTP exemptions, so a URL whose userinfo begins with a loopback host can be accepted even when its parsed host is an external non-loopback system. An external party able to supply a URL to OIDC RP-Initiated Logout registration, authorization-server metadata validation, or another call site can bypass the TLS-required guard and cause cleartext redirection or acceptance of cleartext endpoints. The issue does not bypass redirect URI exact matching and does not by itself forge tokens or authenticate users. The vulnerable authlib.common.security.is_secure_transport() implementation in authlib/common/security.py misinterprets the userinfo component before OIDC RP-Initiated Logout dynamic client registration and other consumers enforce transport security. This issue is fixed in version 1.8.0.

References

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