CVE-2026-59200

Pillow: Decompression Bomb DoS via PdfParser.PdfStream.decode()

Published Jul 14, 2026 CVSS 3.1 · 7.5 High EPSS < 1% KEV · Not listed
Description
Pillow is a Python imaging library. From 5.1.0 until 12.3.0, PdfParser.PdfStream.decode() in PIL/PdfParser.py calls zlib.decompress() with bufsize set to the PDF stream Length field without bounding the decompressed output size, allowing a crafted FlateDecode PDF stream to exhaust memory from a small file. This issue is fixed in version 12.3.0.

Remediation

No solution or workaround provided in the CVE record

Tracking

Sign in to view the affected projects.

Advisories

Source ID Title
Github GHSA Github GHSA GHSA-jjj6-mw9f-p565 Pillow: Decompression Bomb DoS via PdfParser.PdfStream.decode()
Ubuntu USN Ubuntu USN USN-8999-1 Pillow vulnerabilities
History
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'poc', '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 5.1.0 until 12.3.0, PdfParser.PdfStream.decode() in PIL/PdfParser.py calls zlib.decompress() with bufsize set to the PDF stream Length field without bounding the decompressed output size, allowing a crafted FlateDecode PDF stream to exhaust memory from a small file. This issue is fixed in version 12.3.0.
Title Pillow: Decompression Bomb DoS via PdfParser.PdfStream.decode()
Weaknesses CWE-400
CWE-770
References
Metrics cvssV3_1

{'score': 7.5, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
GitHub_M
Published
Updated
Jul 14, 2026, 7:52 PM
Reserved
Jul 2, 2026, 7:53 PM
Status
Analyzed
Published
Jul 14, 2026, 5:17 PM
Modified
Oct 24, 2026, 9:10 PM
Severity
Important
Public date
Jul 14, 2026, 4:09 PM