CVE-2026-77219

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.

CVSS v3 7.1 HIGH

7.1^/10

CVSS v3 : HIGH

Vector :

Exploitability : 1.8 / Impact : 5.2

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact HIGH

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://debbugs.gnu.org/cgi/bugreport.cgi?bug=81344
https://github.com/emacs-mirror/emacs/commit/b07e634e4cf45162ae0178e32092b040587f2c6c
https://github.com/emacs-mirror/emacs/releases/tag/emacs-31.0.91
https://www.vulncheck.com/advisories/gnu-emacs-heap-over-read-via-pbm-ppm-pgm-image-loader

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-21 21:17

Updated : 2026-08-21 22:16

NVD link : CVE-2026-77219

Mitre link : CVE-2026-77219

CVE.ORG link : CVE-2026-77219

JSON object : View

Products Affected

No product.

CWE

CWE-125

Out-of-bounds Read

CWE-190

Integer Overflow or Wraparound

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