---
id: CVE-2026-12547
title: >-
  Libsoup: information disclosure in libsoup via soupauthmanager proxy
  credential leak on proxy switch
summary: >-
  SoupAuthManager caches proxy authentication credentials without scoping them
  to the proxy authority (host:port). When the proxy configuration changes
  (e.g., via system settings or WPAD), cached Proxy-Authorization headers from
  the previo…
severity: low
cvss: 3.4
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:N/A:N'
cvssSource: cna
cwe:
  - CWE-201
vendor: Red Hat
product: libsoup3
affected:
  - libsoup3 (all versions)
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: partial
  timestamp: '2026-07-21T19:02:39.410894Z'
published: '2026-07-21'
updated: '2026-11-06'
sourceUpdated: '2026-11-06T17:57:54.406Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-12547'
references:
  - url: 'https://access.redhat.com/security/cve/CVE-2026-12547'
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2489994'
    label: RHBZ#2489994
  - url: 'https://gitlab.gnome.org/GNOME/libsoup/-/work_items/506'
tags:
  - cve.org
epss: 0.00228
epssPercentile: 0.1359
ingestedAt: '2026-11-06T19:01:36.646Z'
---

## Overview

SoupAuthManager caches proxy authentication credentials without scoping them to the proxy authority (host:port). When the proxy configuration changes (e.g., via system settings or WPAD), cached Proxy-Authorization headers from the previous proxy are sent to the new proxy, leaking credentials.

## Affected

- `libsoup3 (all versions)`

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.

### Workarounds

If changing desktop proxy settings, close any applications using libsoup, then restart the application after the setting has been changed.