CVE-2026-56378 ImageMagick - Heap Out-of-Bounds Read in PCD Decoder

What is CVE-2026-56378?

CVE-2026-56378 is a medium-severity memory corruption vulnerability in Imagemagick Imagemagick, published on 21 Jun 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

ImageMagick before 7.1.2-15 (and 6.x before 6.9.13-40) contains a heap out-of-bounds read in the PCD coder's DecodeImage loop. A crafted PCD file can trigger a one-byte heap out-of-bounds read during image decoding, resulting in denial of service and potential disclosure of an adjacent heap byte.

Weakness: CWE-125

Which versions are affected by CVE-2026-56378?

38 open source packages ship an affected version, including Magick.NET-Q16-AnyCPU, Magick.NET-Q16-HDRI-AnyCPU and Magick.NET-Q16-HDRI-OpenMP-arm64. It affects 1 product.

Products include Imagemagick Imagemagick.

How do I fix CVE-2026-56378?

Upgrade Magick.NET-Q16-AnyCPU to 14.10.3 or later.

Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.

Is CVE-2026-56378 being exploited?

There is no known exploitation of CVE-2026-56378 in the wild and no public exploit code.

Other vulnerabilities in Imagemagick Imagemagick

• CVE-2019-19952 Use after free in n/a Critical 9.8
• CVE-2018-16328 Null dereference in n/a Critical 9.8
• CVE-2018-16329 Null dereference in n/a Critical 9.8
• CVE-2017-18210 Null dereference in n/a Critical 9.8
• CVE-2017-14138 Denial of service in n/a Critical 9.8

All Imagemagick Imagemagick vulnerabilities

Sources

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

Also known as CLSA-2026-1790065439, DEBIAN-CVE-2026-56378, ECHO-e8f8-bb4b-0500, GHSA-jmqv-2mx7-544h, GHSA-wgxp-q8xq-wpp9, JLSEC-2026-1059 and 1 more.