CVE-2026-77219 GNU Emacs < 31.0.91 Heap Over-Read via PBM/PPM/PGM Image Loader
An integer overflow in the image loader allows attackers to leak heap memory contents by supplying a crafted image file.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Local or same network only
- Victim action needed
- A user has to click or open something
- Fix
- Available
What is CVE-2026-77219?
CVE-2026-77219 is a medium-severity vulnerability in GNU Emacs, published on 21 Aug 2026. 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
GNU Emacs before 31.0.91 contains an integer overflow in the PBM/PPM/PGM image loader that allows an attacker to leak heap memory contents by supplying a crafted image with large dimensions and an elevated max color index. The image loader multiplies image dimensions and channel count using signed integer arithmetic; for sufficiently large values, the result wraps to a negative number, bypassing the bounds check and causing the pixel reader to access heap memory past the end of the allocated buffer. The over-read contents are interpreted as pixel color values and rendered on screen.
Which versions are affected by CVE-2026-77219?
How do I fix CVE-2026-77219?
Upgrade to a fixed version.
Is CVE-2026-77219 being exploited?
There is no known exploitation of CVE-2026-77219 in the wild and no public exploit code.
Sources
Also known as AZL-96986, DEBIAN-CVE-2026-77219, GHSA-q8pr-2495-3jw7, OESA-2026-4083, UBUNTU-CVE-2026-77219.