Buffer overflow in Python Pillow
CVE-2026-59205
Pillow is a Python imaging library. Prior to 12.3.0, Pillow's ImageCms.ImageCmsTransform.apply(im, imOut) API can trigger controlled native heap corruption when the caller supplies an output image whose mode does not match the transform's declared output mode. This issue is fixed in version 12.3.0.
Vulnerability class: Buffer Overflow
Published · last modified .
CVSS v3 metric
CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.
EPSS exploit prediction
EPSS: 0.004 (31.0th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 31st percentile — 31.0% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.004 · newest: 0.004 · change: 0.000
Affected products
- Python Pillow
- Python-Pillow Pillow — versions < 12.3.0
Weakness classification (CWE)
References
- github.com/python-pillow/Pillow/commit/a9ffc42bedf4fc0a7ef8d6486e7f9e81e3397721 (Patch)
- github.com/python-pillow/Pillow/pull/9715 (Patch, Issue Tracking)
- github.com/python-pillow/Pillow/releases/tag/12.3.0 (Release Notes)
- github.com/python-pillow/Pillow/security/advisories/GHSA-9hw9-ch79-4vh6 (Exploit, Vendor Advisory)
Frequently asked questions
- What is CVE-2026-59205?
- CVE-2026-59205 is a high-severity vulnerability in Python Pillow, classified under Out-of-bounds Write. CVSS score: 7.5/10. Published 2026-07-14.
- How severe is CVE-2026-59205?
- High severity. CVSS v3 base score is 7.5 out of 10.