CVE-2026-40492: critical vulnerability in HappySeaFox sail
SAIL has heap buffer overflow in XWD decoder — bits_per_pixel vs pixmap_depth type confusion in byte-swap
Published · Updated
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28Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 9.8epss 0.4%
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:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Affected products
HappySeaFox · sailRelated CVEs — HappySeaFox sail
In the same product, most dangerous first.
CVE-2026-54627CRITICALSAIL: Heap out-of-bounds write in SAIL PSD decoder (Bitmap mode ignores depth)EPSS 0.8%CVE-2026-54626CRITICALSAIL: Heap out-of-bounds write in SAIL TGA decoder (indexed-RLE bpp/stride mismatch)EPSS 0.8%CVE-2026-27168HIGHSAIL: Heap-based Buffer Overflow in Sail-codecs-xwdEPSS 0.4%CVE-2026-40493CRITICALSAIL has heap buffer overflow in PSD decoder — bpp mismatch in LAB 16-bit modeEPSS 0.4%CVE-2026-40494CRITICALSAIL has heap buffer overflow in TGA RLE decoder — raw packet path missing bounds checkEPSS 0.3%CVE-2026-54692HIGHSAIL: XBM X10 decoder writes 2 bytes per literal into a 1-byte-per-literal buffer (heap out-of-bounds write)EPSS 0.2%