CVE-2026-59197
HIGHPillow: Heap out-of-bounds write in Pillow `ImageFilter.RankFilter` via integer overflow in `ImagingExpand`
Title source: cnaDescription
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.
References (4)
Core 4
Core References
X_Refsource_Confirm x_refsource_confirm
https://github.com/python-pillow/Pillow/security/advisories/GHSA-xj96-63gp-2gmr
X_Refsource_Misc x_refsource_misc
https://github.com/python-pillow/Pillow/pull/9695
X_Refsource_Misc x_refsource_misc
https://github.com/python-pillow/Pillow/commit/cce3bdb867c77a3420261ed1bfdb6b0787ec8fc1
X_Refsource_Misc x_refsource_misc
https://github.com/python-pillow/Pillow/releases/tag/12.3.0
Scores
CVSS v3
8.2
EPSS
0.0044
EPSS Percentile
35.9%
Attack Vector
NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H
CISA SSVC
Vulnrichment
Exploitation
poc
Automatable
yes
Technical Impact
partial
Details
CWE
CWE-190
CWE-787
Status
published
Products (3)
pypi/Pillow
0 - 12.3.0PyPI
python/pillow
< 12.3.0
python-pillow/Pillow
< 12.3.0
Published
Jul 14, 2026
Tracked Since
Jul 14, 2026