CVE-2026-4271

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).

This MODERATE impact use-after-free flaw in libsoup's HTTP/2 server implementation affects applications that use libsoup to handle HTTP/2 server callbacks. An attacker can trigger this by sending HTTP/2 requests that cause authentication validation failures, potentially leading to application instability or crashes. Red Hat products are affected if they leverage libsoup as an HTTP/2 server and disconnect client connections during header processing.

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.

Mitigation for this issue is either not available or the currently available options don't meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.