Buffer overflow in Happyseafox Sail
CVE-2026-40494
SAIL is a cross-platform library for loading and saving images with support for animation, metadata, and ICC profiles. Prior to commit 45d48d1f2e8e0d73e80bc1fd5310cb57f4547302, the TGA codec's RLE decoder in `tga.c` has an asymmetric bounds check vulnerability. The run-packet path (line 297) correctly clamps the repeat count to the remaining buffer space, but the raw-packet path (line 305-311) has no equivalent bounds check. This allows writing up to 496 bytes of attacker-controlled data past the end of a heap buffer. Commit 45d48d1f2e8e0d73e80bc1fd5310cb57f4547302 patches the issue.
Vulnerability class: Buffer Overflow
EPSS: 0.003 (23.8th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.
Affected products
- Happyseafox Sail — versions < 45d48d1f2e8e0d73e80bc1fd5310cb57f4547302
Weakness classification (CWE)
References
- security-advisories@github.com (x_refsource_CONFIRM)
- security-advisories@github.com (x_refsource_MISC)
Frequently asked questions
- What is CVE-2026-40494?
- CVE-2026-40494 is a critical-severity vulnerability in Happyseafox Sail, classified under Out-of-bounds Write. CVSS score: 9.8/10. Published 2026-04-18.
- How severe is CVE-2026-40494?
- Critical severity. CVSS v3 base score is 9.8 out of 10.