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.
History

Fri, 21 Aug 2026 22:30:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}


Fri, 21 Aug 2026 21:45:00 +0000

Type Values Removed Values Added
First Time appeared Gnu
Gnu emacs
Vendors & Products Gnu
Gnu emacs

Fri, 21 Aug 2026 20:45:00 +0000

Type Values Removed Values Added
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.
Title GNU Emacs < 31.0.91 Heap Over-Read via PBM/PPM/PGM Image Loader
Weaknesses CWE-125
CWE-190
References
Metrics cvssV3_1

{'score': 7.1, 'vector': 'CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:H'}

cvssV4_0

{'score': 6.9, 'vector': 'CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:H/VI:N/VA:H/SC:N/SI:N/SA:N'}


cve-icon MITRE

Status: PUBLISHED

Assigner: VulnCheck

Published:

Updated: 2026-08-21T21:42:58.824Z

Reserved: 2026-08-20T18:25:46.943Z

Link: CVE-2026-77219

cve-icon Vulnrichment

Updated: 2026-08-21T21:32:46.866Z

cve-icon NVD

Status : Received

Published: 2026-08-21T21:17:06.590

Modified: 2026-08-21T22:16:45.797

Link: CVE-2026-77219

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-08-21T22:30:17Z