CVE-2026-42309

Pillow: Heap buffer overflow with nested list coordinates

Published May 9, 2026 CVSS 4.0 · 5.1 Medium EPSS < 1% KEV · Not listed
Description
Pillow is a Python imaging library. From version 11.2.1 to before version 12.2.0, passing nested lists as coordinates to APIs that accept coordinates such as ImagePath.Path, ImageDraw.ImageDraw.polygon and ImageDraw.ImageDraw.line could cause a heap buffer overflow, as nested lists were recursively unpacked beyond the allocated buffer. Coordinate lists are now validated to contain exactly two numeric coordinates. This issue has been patched in version 12.2.0.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

Source ID Title
Github GHSA Github GHSA GHSA-5xmw-vc9v-4wf2 Pillow has a heap buffer overflow with nested list coordinates
Ubuntu USN Ubuntu USN USN-8399-1 Pillow vulnerabilities
History
Type Values Removed Values Added
First Time appeared Python
Python pillow
CPEs cpe:2.3:a:python:pillow:*:*:*:*:*:*:*:*
Vendors & Products Python
Python pillow
Metrics cvssV3_1

{'score': 5.5, 'vector': 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H'}

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
First Time appeared Python-pillow
Python-pillow pillow
Vendors & Products Python-pillow
Python-pillow pillow
Type Values Removed Values Added
Description Pillow is a Python imaging library. From version 11.2.1 to before version 12.2.0, passing nested lists as coordinates to APIs that accept coordinates such as ImagePath.Path, ImageDraw.ImageDraw.polygon and ImageDraw.ImageDraw.line could cause a heap buffer overflow, as nested lists were recursively unpacked beyond the allocated buffer. Coordinate lists are now validated to contain exactly two numeric coordinates. This issue has been patched in version 12.2.0.
Title Pillow: Heap buffer overflow with nested list coordinates
Weaknesses CWE-122
References
Metrics cvssV4_0

{'score': 5.1, 'vector': 'CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
GitHub_M
Published
Updated
May 11, 2026, 2:48 PM
Reserved
Apr 26, 2026, 12:37 PM
Status
Analyzed
Published
May 9, 2026, 6:16 AM
Modified
Jul 24, 2026, 9:10 PM
Severity
Moderate
Public date
May 9, 2026, 4:08 AM