Medium severity · published Oct 28, 2026
CVE-2026-59959
SAIL: WebP decoder division by zero through malformed animated canvas metadata
New
4.8
CVSS
–
EPSS
No
On KEV
Description
SAIL is a cross-platform library for loading and saving images with support for animation, metadata, and ICC profiles. Prior to version 1.0.2, the built-in WebP decoder can crash during loader initialization when processing a malformed animated WebP file with inconsistent container or `ANMF` frame metadata. In `sail_codec_load_init_v8_webp()` in `src/sail-codecs/webp/webp.c`, `WebPDemuxGetI` with `WEBP_FF_CANVAS_WIDTH` can return a zero `image_local->width`, which is then used as a divisor when calculating `bytes_per_pixel` from the image row size. The division happens before frame decoding and before generic image skeleton validation in `src/sail/sail_advanced.c`, causing an arithmetic fault and process termination. Applications accepting untrusted WebP images can consequently suffer denial of service; builds must include the affected WebP codec. This issue is fixed in version 1.0.2.
Exploitation
Is it being used?
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
SA
sail · HappySeaFox
< 1.0.2 · source: vendor
Affected product
SA
sail
HappySeaFox
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