Critical Severity Vulnerability
This vulnerability has been rated as Critical severity. Immediate action is recommended.
CVE-2026-40492
CriticalVulnerability Description
SAIL is a cross-platform library for loading and saving images with support for animation, metadata, and ICC profiles. Prior to commit 36aa5c7ec8a2bb35f6fb867a1177a6f141156b02, the XWD codec resolves pixel format based on `pixmap_depth` but the byte-swap code uses `bits_per_pixel` independently. When `pixmap_depth=8` (BPP8_INDEXED, 1 byte/pixel buffer) but `bits_per_pixel=32`, the byte-swap loop accesses memory as `uint32_t*`, reading/writing 4x the allocated buffer size. This is a different vulnerability from the previously reported GHSA-3g38-x2pj-mv55 (CVE-2026-27168), which addressed `bytes_per_line` validation. Commit 36aa5c7ec8a2bb35f6fb867a1177a6f141156b02 contains a patch.
CVSS Metrics
Common Vulnerability Scoring System
Vector String:
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Severity Details
Weakness Type (CWE)
Out-of-bounds Write
- Description
- The product writes data past the end, or before the beginning, of the intended buffer.
- Exploit Likelihood
- High
- Typical Severity
- High
- Abstraction Level
- Base
Key Information
- Published Date
- April 18, 2026
