Log in Start free

Vulnerability · Published Oct 14, 2026 · Assigned by VulnCheck

CVE-2026-110601libsixel before 1.8.7-r1 and 1.9.0 through 1.10.5 Heap Out-of-Bounds Write via GIF

Medium 6.3

In plain English

A medium-severity out-of-bounds write in libsixel from saitoha. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 15% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 3.1)6.3Medium
Exploit odds (30 days)0.2%top 85.3% of all CVEs
Exploited in the wildNo reportsCISA SSVC: poc
Attack toolingNoneno public tooling known

Official description

libsixel before 1.8.7-r1 and 1.9.0 through 1.10.5 contains a heap out-of-bounds write vulnerability in gif_init_frame() in src/fromgif.c, which never checks the GIF transparent color index against the palette size. Attackers can supply a crafted GIF with a small color table and large transparent index, processed with a background color set, to write bytes past the palette buffer, causing heap corruption or crashes.

Affected packages & fixed versions

EcosystemPackageFixed inAdvisory
Debian:12libsixelno fix listedDEBIAN-CVE-2026-110601
Debian:13libsixelno fix listedDEBIAN-CVE-2026-110601
Debian:14libsixel1:1.8.7-r2-1DEBIAN-CVE-2026-110601
Ubuntu:22.04:LTSlibsixelno fix listedUBUNTU-CVE-2026-110601
Ubuntu:24.04:LTSlibsixelno fix listedUBUNTU-CVE-2026-110601
Ubuntu:26.04:LTSlibsixelno fix listedUBUNTU-CVE-2026-110601
Ubuntu:26.10libsixelno fix listedUBUNTU-CVE-2026-110601

Affected products (as reported)

VendorProductVersions
saitoha libsixel 0 – before 1.8.7-r11.9.0 – through 1.10.5

Weakness: CWE-787 · Vector: CVSS:3.1/AV:L/AC:H/PR:N/UI:R/S:U/C:N/I:H/A:H

References