Bug 2559389 (CVE-2026-114614)

Summary:	CVE-2026-114614 authlib: Authlib: Transport security bypass via improper URL validation
Product:	[Other] Security Response	Reporter:	OSIDB Bzimport <bzimport>
Component:	vulnerability	Assignee:	Product Security DevOps Team <prodsec-dev>
Status:	NEW ---	QA Contact:
Severity:	low	Docs Contact:
Priority:	low
Version:	unspecified	CC:	anpicker, anthomas, dfreiber, dkeler, doconnor, drow, dschmidt, ebourniv, ehelms, ggainey, hasun, ilpinto, jburrell, jfula, jlanda, jowilson, jpasqual, juwatts, kshier, lblicha, ltomasbo, mdellweg, mhayden, mhulan, nmoumoul, nyancey, ogajduse, ometelka, osousa, pcreech, ptisnovs, rbobbitt, rchan, rjohnson, sbunciak, sdoran, simaishi, smallamp, stcannon, suppawar, syedriko, thason, tmalecek, vkumar, xdharmai, yguenane, ykashtan, zhunting
Target Milestone:	---	Keywords:	Security
Target Release:	---
Hardware:	All
OS:	Linux
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Doc Text:	A flaw was found in Authlib. The library's transport security verification improperly validates web addresses by using prefix matching to exempt local loopback addresses from encryption requirements. A remote attacker can exploit this issue by supplying a crafted URL containing local host information in the user credentials field to bypass Transport Layer Security (TLS) enforcement. This flaw can lead to the acceptance of unencrypted connections or redirection to external cleartext servers, potentially exposing sensitive information in transit.	Story Points:	---
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oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:
Bug Depends On:	2568066, 2568067, 2568068, 2568069, 2568070
Bug Blocks:

Description OSIDB Bzimport 2026-10-22 21:12:21 UTC

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.