CVE-2026-59197
Pillow: Heap out-of-bounds write in Pillow `ImageFilter.RankFilter` via integer overflow in `ImagingExpand`
Vexday Risk Score
18Low
SSVC decision (CISA)
Track
No exploitation signal → monitor
CVSS 8.2EPSS —KEV nãoPoC —Nuclei —Metasploit —Patch —
Lifecycle
14 Jul 2026Published on NVD
Recommendation: Monitor — no exploitation signal at the moment.
Pillow is a Python imaging library. Prior to 12.3.0, Pillow's public rank-filter API can trigger a native heap out-of-bounds write when given a very large odd filter size because ImageFilter.RankFilter.filter() calls image.expand(size // 2, size // 2) before rank-filter size validation and ImagingExpand() computes output dimensions with unchecked signed int arithmetic. This issue is fixed in version 12.3.0.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H
Affected products
python-pillow · Pillow