CVE-2026-40493 (GCVE-0-2026-40493)

Vulnerability from cvelistv5 – Published: 2026-04-18 01:41 – Updated: 2026-04-20 16:15
VLAI
Title
SAIL has heap buffer overflow in PSD decoder — bpp mismatch in LAB 16-bit mode
Summary
SAIL is a cross-platform library for loading and saving images with support for animation, metadata, and ICC profiles. Prior to commit c930284445ea3ff94451ccd7a57c999eca3bc979, the PSD codec computes bytes-per-pixel (`bpp`) from raw header fields `channels * depth`, but the pixel buffer is allocated based on the resolved pixel format. For LAB mode with `channels=3, depth=16`, `bpp = (3*16+7)/8 = 6`, but the format `BPP40_CIE_LAB` allocates only 5 bytes per pixel. Every pixel write overshoots, causing a deterministic heap buffer overflow on every row. Commit c930284445ea3ff94451ccd7a57c999eca3bc979 contains a patch.
Severity
9.8 (Critical)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
SSVC
Exploitation: poc Automatable: yes Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-04-20 16:11 UTC
CWE
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 8026 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
HappySeaFox sail Affected: < c930284445ea3ff94451ccd7a57c999eca3bc979
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

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