CVE-2026-33019

The record

libsixel is a SIXEL encoder/decoder implementation derived from kmiya's sixel. Versions 1.8.7 and prior contain an integer overflow leading to an out-of-bounds heap read in the --crop option handling of img2sixel, where positive coordinates up to INT_MAX are accepted without overflow-safe bounds checking. In sixel_encoder_do_clip(), the expression clip_w + clip_x overflows to a large negative value when clip_x is INT_MAX, causing the bounds guard to be skipped entirely, and the unclamped coordinate is passed through sixel_frame_clip() to clip(), which computes a source pointer far beyond the image buffer and passes it to memmove(). An attacker supplying a specially crafted crop argument with any valid image can trigger an out-of-bounds read in the heap, resulting in a reliable crash and potential information disclosure. This issue has been fixed in version 1.8.7-r1.

Affected packages

Related vulnerabilities

• CVE-2026-92824 A flaw was found in libmodulemd. CWE-125
• CVE-2026-114038 A flaw was found in device-mapper-multipath. CWE-125
• CVE-2026-112896 Pillow is a Python imaging library. CWE-125
• CVE-2026-112278 rdesktop through 1.9.0 contains a heap out-of-bounds read vulnerability in… CWE-125
• CVE-2026-112273 libtins through 4.6 contains a heap out-of-bounds read vulnerability in DNS::compose_name… CWE-125
• CVE-2026-112073 A vulnerability was identified in Tencent ncnn up to 44b02dabdcf97499281a4692ebd65bad73dc… CWE-125
• CVE-2026-112020 LodePNG through 20261006 contains a heap out-of-bounds read vulnerability in… CWE-125
• CVE-2026-88842 A flaw was found in BusyBox dpkg. CWE-125