Vulnerability Report

CVE-2026-4271

Title: libsoup Use-After-Free in HTTP/2 Server

Memory Corruption

Proof Of Concept

No public PoC currently indexed for CVE-2026-4271.

CWE Category CWE-416

Published Date Mar 17, 2026

Modified Date May 19, 2026

Exploit Status Not Found

Score 5.3 CVSS v3.1

Exploit Probability (EPSS)

0.93%

Vulnerability Summary

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).

Impacted Vendors

libsoup 1

gnome 1

Reference Links

https://access.redhat.com/security/cve/CVE-2026-4271 https://bugzilla.redhat.com/show_bug.cgi?id=2448044 https://gitlab.gnome.org/GNOME/libsoup/-/issues/496

CVSS v3.1

Source Entity [email protected]

Severity MEDIUM

5.3

Attack Vector

NETWORK

Complexity

LOW

Privileges

N/A

Interaction

NONE

Confidentiality

N/A

Integrity

N/A

Availability

N/A

Scope

UNCHANGED

RAW VECTOR CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L