CVE-2026-55380 PUBLISHED

Pillow GdImageFile decompression bomb protection bypass

Assigner: GitHub_M
Reserved: 16.06.2026 Published: 06.07.2026 Updated: 06.07.2026

Pillow is a Python imaging library. Prior to 12.3.0, PIL/GdImageFile.py GdImageFile._open() read image dimensions from the GD 2.x header and stored them in self._size without calling Image._decompression_bomb_check(), allowing a crafted .gd file to trigger excessive C-heap allocation when loaded. This issue is fixed in version 12.3.0.

Metrics

CVSS 3.1

CVSS Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CVSS Score: 7.5

Attack Vector	Network	Scope	Unchanged
Attack Complexity	Low	Confidentiality Impact	None
Privileges Required	None	Integrity Impact	None
User Interaction	None	Availability Impact	High

CVSS 3.1

Product Status

Vendor	python-pillow
Product	Pillow
Versions	Version < 12.3.0 is affected

References

https://github.com/python-pillow/Pillow/security/advisories/GHSA-phj9-mv4w-65pm
https://github.com/python-pillow/Pillow/commit/f39b0ae6624eb2d7c5c5d651d9bb5fdbd96a8675
https://github.com/python-pillow/Pillow/blob/main/docs/releasenotes/12.3.0.rst

Problem Types

CWE-789: Memory Allocation with Excessive Size Value CWE