CVE-2026-110601
libsixel before 1.8.7-r1 and 1.9.0 through 1.10.5 Heap Out-of-Bounds Write via GIF
CVSS Score
6.3
EPSS Score
0.0%
EPSS Percentile
0th
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.
| CWE | CWE-787 |
| Vendor | saitoha |
| Product | libsixel |
| Published | Oct 14, 2026 |
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CVSS v3 Breakdown
CVSS:3.1/AV:L/AC:H/PR:N/UI:R/S:U/C:N/I:H/A:H Attack Vector
Local
Attack Complexity
High
Privileges Required
None
User Interaction
Required
Scope
Unchanged
Confidentiality
None
Integrity
High
Availability
High
Affected Versions
saitoha / libsixel
0 < 1.8.7-r1 1.9.0 ≤ 1.10.5
References
github.com: https://github.com/saitoha/libsixel/issues/220 github.com: https://github.com/saitoha/libsixel/commit/bdbab09816eb9188429c37a50b97c5e66dfe5047 github.com: https://github.com/saitoha/libsixel/releases/tag/v1.8.7-r1 github.com: https://github.com/saitoha/libsixel/blob/v1.8.7/src/fromgif.c#L182-L248 github.com: https://github.com/libsixel/libsixel/blob/v1.10.5/src/fromgif.c#L219-L240 hackmd.io: https://hackmd.io/@haind-pwn/libsixel-gif-transparent-index-oob-write vulncheck.com: 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
Credits
ShangzhiXu HaiND from the Post and Telecommunication Institute of Technology