CVE-2025-66019 - Vulnerability Details - OpenCVE

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.

Attack Vector Network

Attack Complexity Low

Privileges Required None

Attack Requirements None

User Interaction None

Vulnerable System Confidentiality Impact None

Vulnerable System Integrity Impact None

Vulnerable System Availability Impact High

Subsequent System Confidentiality Impact None

Subsequent System Integrity Impact None

Subsequent System Availability Impact None

No CVSS v3.1

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

No EPSS score available.

Key SSVC decision points have not yet been added.

No data.

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Advisories

No advisories yet.

Fixes

Solution

No solution given by the vendor.

Workaround

No workaround given by the vendor.

References

Link	Providers
https://github.com/py-pdf/pypdf/commit/96186725e5e6f237129a58a97cd19204a9ce40b2
https://github.com/py-pdf/pypdf/releases/tag/6.4.0
https://github.com/py-pdf/pypdf/security/advisories/GHSA-m449-cwjh-6pw7

History

Tue, 25 Nov 2025 23:45:00 +0000

Type	Values Removed	Values Added
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.
Title		pypdf manipulated LZWDecode streams can exhaust RAM
Weaknesses		CWE-400 CWE-409
References		https://github.com/py-pdf/pypdf/commit/96186725e5e6f237129a58a97cd19204a9ce40b2 https://github.com/py-pdf/pypdf/releases/tag/6.4.0 https://github.com/py-pdf/pypdf/security/advisories/GHSA-m449-cwjh-6pw7
Metrics		cvssV4_0 `{'score': 6.6, 'vector': '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'}`

MITRE

Status: PUBLISHED

Assigner: GitHub_M

Published: 2025-11-25T23:38:12.473Z

Updated: 2025-11-25T23:38:12.473Z

Reserved: 2025-11-21T01:08:02.613Z

Link: CVE-2025-66019

Vulnrichment

No data.

NVD

Status : Received

Published: 2025-11-26T00:15:51.263

Modified: 2025-11-26T00:15:51.263

Link: CVE-2025-66019

Redhat

No data.

OpenCVE Enrichment

No data.

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