CVE-2026-86421 ImageMagick before 7.1.2-30 Memory Leak via MSL decoder
A memory leak in the MSL decoder allows attackers to exhaust system memory and cause denial of service via crafted images.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-86421?
CVE-2026-86421 is a medium-severity denial of service vulnerability in Imagemagick Imagemagick, published on 7 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
ImageMagick before 7.1.2-30 and 6.9.13-55 contains a memory leak in the MSL image decoder. A crafted MSL image triggers memory allocation without proper deallocation, allowing an attacker to exhaust memory and cause a denial of service.
Weakness: CWE-400
Which versions are affected by CVE-2026-86421?
It affects 1 product.
Products include Imagemagick Imagemagick.
How do I fix CVE-2026-86421?
Upgrade to a fixed version.
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-2026-86421 being exploited?
There is no known exploitation of CVE-2026-86421 in the wild and no public exploit code.
Other vulnerabilities in Imagemagick Imagemagick
Sources
Also known as CLSA-2026-1789486747, CLSA-2026-1789565568, CLSA-2026-1791925507, DEBIAN-CVE-2026-86421, ECHO-435d-018f-25c9, GHSA-4jv7-q6xw-6f4x and 3 more.