CVE-2026-110601

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.

CVSS v3 6.3 MEDIUM

6.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.0 / Impact : 5.2

Attack Vector LOCAL

Attack Complexity HIGH

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact NONE

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/libsixel/libsixel/blob/v1.10.5/src/fromgif.c#L219-L240
https://github.com/saitoha/libsixel/blob/v1.8.7/src/fromgif.c#L182-L248
https://github.com/saitoha/libsixel/commit/bdbab09816eb9188429c37a50b97c5e66dfe5047
https://github.com/saitoha/libsixel/issues/220
https://github.com/saitoha/libsixel/releases/tag/v1.8.7-r1
https://hackmd.io/@haind-pwn/libsixel-gif-transparent-index-oob-write
https://www.vulncheck.com/advisories/libsixel-before-1.8.7-r1-and-1.9.0-through-1.10.5-heap-out-of-bounds-write-via-gif
https://github.com/saitoha/libsixel/issues/220

Configurations

No configuration.

History

20 Oct 2026, 01:17

Type	Values Removed	Values Added
References	~~() https://github.com/saitoha/libsixel/issues/220 -~~	() https://github.com/saitoha/libsixel/issues/220 -

14 Oct 2026, 15:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-14 15:17

Updated : 2026-10-20 01:17

NVD link : CVE-2026-110601

Mitre link : CVE-2026-110601

CVE.ORG link : CVE-2026-110601

JSON object : View

Products Affected

No product.

CWE

CWE-787

Out-of-bounds Write

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