CVE-2026-12547 Libsoup: information disclosure in libsoup via soupauthmanager proxy credential leak on proxy switch
Attackers can steal proxy credentials when the proxy configuration changes because libsoup fails to scope cached authentication headers to the specific proxy authority.
- Exploited in the wild
- Not known
- Login needed
- An administrator
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- Available
What is CVE-2026-12547?
CVE-2026-12547 is a low-severity vulnerability in Red Hat Enterprise Linux 10, published on 21 Jul 2026. An attacker needs administrator access to exploit it, and only if a user opens a file or follows a link.
Official description
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.
Weakness: CWE-201
Which versions are affected by CVE-2026-12547?
How do I fix CVE-2026-12547?
Apply the vendor's patch.
Is CVE-2026-12547 being exploited?
There is no known exploitation of CVE-2026-12547 in the wild and no public exploit code.
Sources
Also known as AZL-93237, DEBIAN-CVE-2026-12547, ECHO-d505-ef7c-089c, GHSA-gmf9-8jmv-v2q8, OESA-2026-4388, UBUNTU-CVE-2026-12547.