CVE-2025-66019

MEDIUM

pypdf < 6.4.0 - Uncontrolled Resource Consumption via LZWDecode Filter

Title source: llm
STIX 2.1

Description

pypdf is a free and open-source pure-python PDF library. Prior to version 6.4.0, an attacker who uses this vulnerability can craft a PDF which leads to a memory usage of up to 1 GB per stream. This requires parsing the content stream of a page using the LZWDecode filter. This issue has been patched in version 6.4.0.

References (4)

Core 4

Scores

CVSS v4 6.6
EPSS 0.0030
EPSS Percentile 21.6%
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

CISA SSVC

Vulnrichment
Exploitation none
Automatable yes
Technical Impact partial

Details

CWE
CWE-400 CWE-409
Status published
Products (2)
py-pdf/pypdf < 6.4.0
pypi/pypdf 0 - 6.4.0PyPI
Published Nov 26, 2025
Tracked Since Feb 18, 2026