CVE-2026-4271

What it is

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).

At a glance

Exploitability

Can be exploited over the network without logging in. Limited direct impact.

Exploit odds

0.9% chance of exploitation in the next 30 days (EPSS).

Fix

A patch, advisory or fixed version is referenced. Upgrade or apply it.

Timeline

1. 2026-03-17 12:16 UTC PublishedDisclosed publicly on CVE.org and NVD
2. 2026-11-05 21:18 UTC Last updatedMost recent change to the record

Details

Published

2026-03-17 12:16 UTC

Last modified

2026-11-05 21:18 UTC

Exploit probability

0.9% · EPSS, next 30 days

Weakness

CWE-416 · Use after free

Record status

Modified

Affected

• Gnome Libsoup
• Redhat Enterprise Linux 6.0
• Redhat Enterprise Linux 7.0
• Redhat Enterprise Linux 8.0
• Redhat Enterprise Linux 9.0
• Redhat Enterprise Linux 10.0

Attack profile CVSS 3.1 · 5.3

Attack vector

Network

Complexity

Low

Privileges needed

None

User interaction

None

Scope

Unchanged

Confidentiality

None

Integrity

None

Availability

Low