CVE-2026-96638

MEDIUM
MEDIUM Priority: 0.02 BB Relevance: 63/100
Published: 2026-10-21 Modified: 2026-10-28 First seen: 2026-10-29 Status: active

Attack Surface

Network Low Complexity No Auth

CVSS Vector Breakdown

AV: Network
AC: Low
PR: None
UI: Required
S: Unchanged
C: None
I: None
A: High

Description

Pillow is a Python imaging library. From 9.1.0 until 13.0.0, BmpRleDecoder.decode() in src/PIL/BmpImagePlugin.py permits crafted RLE BMP delta escapes and absolute-mode runs to append beyond the remaining dest_length without a per-branch cap. A delta can add roughly 255 image rows in one iteration, so a kilobyte-sized file with a large but permitted width can expand the data bytearray to hundreds of megabytes or more, causing memory-exhaustion denial of service. This issue is fixed in version 13.0.0.

Weakness Classification (2)

Affected Software (2)

VendorProductVersion
python pillow 9.1.0 – 13.0.0
python-pillow Pillow >= 9.1.0, < 13.0.0

Bug Bounty Relevance

63 / 100
✓ Network accessible
✓ No authentication
✓ Low complexity

CVSS Score

6.5 / 10.0 v3.1
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H

EPSS — Exploitation Probability

0.34%
Raw Score 0.003450
Percentile 28.0%
Date 2026-10-29

EPSS Trend

2026-10-29
0.00345
2026-10-28
0.00345

Intelligence Sources

mitre ref →
nvd ref →