CVE-2026-114614

Authlib: is_secure_transport() loopback exemption can be bypassed with a userinfo component, allowing cleartext-HTTP URLs to non-loopback hosts

LOW
3.5
CVSS Score
Published: October 22, 2026 at 09:00 PM UTC
Updated: October 29, 2026 at 02:48 PM UTC
1 product affected across 1 vendorAuthlib

Using authlib by authlib?

Get instant alerts when new vulnerabilities affect authlib - before attackers find them.

Real-time alertsTrack your software stackFree plan available
Severity
LOW3.5
Exploit prediction
EPSS 0.3%
SSVC
PoC

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.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

0.13 ≤ v < 1.8.0

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

References (3)

x_refsource_CONFIRMExploitMitigationVendor Advisory
Source: cverecord
https://github.com/authlib/authlib/security/advisories/GHSA-jj7h-c3hg-m23x
x_refsource_MISCRelease Notes
Source: cverecord
https://github.com/authlib/authlib/releases/tag/v1.8.0

SSVC — Action Prioritization

SSVCPoCNot automatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

Attack Vector
NETWORK
Complexity
LOW
Privileges
LOW
User Interaction
REQUIRED
Scope
UNCHANGED
Confidentiality
LOW
Integrity
NONE
Availability
NONE
Vector?

Quick Info

StatusANALYZED
CWE
CWE-601CWE-693

Get alerted

Stop reading CVE feeds looking for your own stack

Track the products you run and VulnTracker tells you when a new CVE affects them — with what is known about fixing it, and nothing about the rest.

Free plan, no card