What’s Vulnerable › Vulnerabilities

CVE-2026-59199: Pillow: Heap out-of-bounds write `Image.paste()` / `Image.crop()` via signed coordinate overflow

• Severity: high (CVSS 7.5 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.4% probability of exploitation in the next 30 days
• Public exploit or detection template: yes
• Published: 2026-07-14 · updated 2026-10-24
• Weakness: CWE-190

Description

Pillow is a Python imaging library. Prior to 12.3.0, Pillow public image coordinate APIs can trigger a native heap out-of-bounds write when given coordinates near the signed 32-bit integer limits in Image.paste(), Image.crop(), or Image.alpha_composite(). This issue is fixed in version 12.3.0.

Affected products

• python-pillow Pillow: before 12.3.0 — fixed in 12.3.0
• Pypi Pillow: before 12.3.0; 1.0, 1.1, 1.2, 1.3, 1.4, 1.5 (+100) — fixed in 12.3.0

How to fix

Upgrade to a fixed version: python-pillow Pillow 12.3.0; Pypi Pillow 12.3.0. Check the vendor advisory for mitigations.

References

• https://github.com/python-pillow/Pillow/commit/ceefc348eb3c3844c7f9796ef2cc3a7dd5fbba7b
• https://github.com/python-pillow/Pillow/pull/9703
• https://github.com/python-pillow/Pillow/releases/tag/12.3.0
• https://github.com/python-pillow/Pillow/security/advisories/GHSA-6r8x-57c9-28j4
• https://github.com/python-pillow/Pillow/security/advisories/GHSA-6r8x-57c9-28j4

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