CVE-2023-43786 Libx11: stack exhaustion from infinite recursion in putsubimage()

What is CVE-2023-43786?

CVE-2023-43786 is a medium-severity denial of service vulnerability in Fedoraproject Fedora, published on 10 Oct 2023. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link.

Official description

A vulnerability was found in libX11 due to an infinite loop within the PutSubImage() function. This flaw allows a local user to consume all available system resources and cause a denial of service condition.

Weakness: CWE-835, CWE-400

Which versions are affected by CVE-2023-43786?

It affects 3 products.

Products include Fedoraproject Fedora, Redhat Enterprise Linux, X.org Libx11.

How do I fix CVE-2023-43786?

Apply the vendor's patch.

Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.

Is CVE-2023-43786 being exploited?

There is no known exploitation of CVE-2023-43786 in the wild and no public exploit code.

Public exploit code: 1 proofs of concept on GitHub.

Other vulnerabilities in Fedoraproject Fedora

• CVE-2024-4577 PHP-CGI OS Command Injection Exploited Critical 9.8
• CVE-2021-39226 Grafana Authentication Bypass Exploited Critical 9.8
• CVE-2019-5544 VMware ESXi and Horizon DaaS OpenSLP Heap-Based Buffer Overflow Exploited Critical 9.8
• CVE-2024-4947 Google Chromium V8 Type Confusion Exploited Critical 9.6
• CVE-2024-4671 Google Chromium Visuals Use-After-Free Exploited Critical 9.6

All Fedoraproject Fedora vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as ALPINE-CVE-2023-43786, AZL-31321, BELL-CVE-2023-43786, CLSA-2025-1745529850, DEBIAN-CVE-2023-43786, GHSA-35w7-h3v9-8qw4 and 2 more.