CVE-2026-55379

Pillow is a Python imaging library. Prior to 12.3.0, PIL/BdfFontFile.py bdf_char() read the BBX width and height field from a BDF font file and passed attacker-controlled dimensions to Image.new() without calling Image._decompression_bomb_check(), bypassing Pillow's documented decompression bomb protection and allowing excessive memory allocation. This issue is fixed in version 12.3.0.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/python-pillow/Pillow/blob/main/docs/releasenotes/12.3.0.rst	Release Notes
https://github.com/python-pillow/Pillow/commit/0a263e6264aa5399988d9acd3bbfbca2ca3ec77d	Patch
https://github.com/python-pillow/Pillow/security/advisories/GHSA-45hq-cxwh-f6vc	Exploit Vendor Advisory
https://github.com/python-pillow/Pillow/security/advisories/GHSA-45hq-cxwh-f6vc	Exploit Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:python:pillow:*:*:*:*:*:*:*:*

History

25 Oct 2026, 20:10

Type	Values Removed	Values Added
Summary		(es) Pillow es una biblioteca de procesamiento de imágenes de Python. Antes de la versión 12.3.0, PIL/BdfFontFile.py bdf_char() leía los campos de ancho y alto BBX de un archivo de fuente BDF y pasaba dimensiones controladas por el atacante a Image.new() sin llamar a Image._decompression_bomb_check(), eludiendo la protección contra bombas de descompresión documentada de Pillow y permitiendo una asignación excesiva de memoria. Este problema está solucionado en la versión 12.3.0.

Information

Published : 2026-07-06 19:17

Updated : 2026-10-25 20:10

NVD link : CVE-2026-55379

Mitre link : CVE-2026-55379

CVE.ORG link : CVE-2026-55379

JSON object : View

Products Affected

python

pillow

CWE

CWE-789

Memory Allocation with Excessive Size Value

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