CVE-2026-4271
MEDIUM severity · CVSS 5.3 · Use-after-free
5.3CVSS MEDIUM
Summary
A flaw was found in libsoup, a library for handling HTTP requests. This vulnerability, known as a Use-After-Free, occurs in the HTTP/2 server implementation. A remote attacker can exploit this by sending specially crafted HTTP/2 requests that cause authentication failures. This can lead to the application attempting to access memory that has already been freed, potentially causing application instability or crashes, resulting in a Denial of Service (DoS).
Impact & exploitability
Attack vectorNetwork
Attack complexityLow
Privileges requiredNone
User interactionNone
Confidentiality impactNone
Integrity impactNone
Availability impactLow
Exploit probability (EPSS)1%
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
Affected products we track (1)
Recommendation
Apply the vendor fix in your normal patch cycle. Open any affected product above for its exact safe version.
Additional information
- NVD record
- https://access.redhat.com/security/cve/CVE-2026-4271Advisory
- https://bugzilla.redhat.com/show_bug.cgi?id=2448044Advisory
- https://gitlab.gnome.org/GNOME/libsoup/-/issues/496Advisory
- https://access.redhat.com/errata/RHSA-2026:15968
- https://access.redhat.com/errata/RHSA-2026:17482
- https://access.redhat.com/errata/RHSA-2026:19143