CVE-2025-62708: pypdf manipulated LZWDecode streams can exhaust RAM

Published Oct 22, 2025
·
Updated

Impact

An attacker who uses this vulnerability can craft a PDF which leads to large memory usage. This requires parsing the content stream of a page using the LZWDecode filter.

Patches This has been fixed in pypdf==6.1.3.

Workarounds If you cannot upgrade yet, consider applying the changes from PR #3502.

Other sources

pypdf is a free and open-source pure-python PDF library. Prior to version 6.1.3, an attacker who uses this vulnerability can craft a PDF which leads to large memory usage. This requires parsing the content stream of a page using the LZWDecode filter. This has been fixed in pypdf version 6.1.3.

MITRE

Affected Software

2 affected componentsFixes available
pip/pypdf<6.1.3
6.1.3
Pypdf Project Pypdf<6.1.3

Event History

Oct 22, 2025
Advisory Published
via GitHub·07:40 PM
Data Sourced
via GitHub·07:40 PM
DescriptionWeaknessAffected Software
CVE Published
via MITRE·09:36 PM
Data Sourced
via MITRE·09:36 PM
DescriptionWeakness
Data Sourced
via NVD·10:15 PM
RemedyDescriptionSeverityWeaknessAffected Software

Frequently Asked Questions

1

What is the severity of CVE-2025-62708?

CVE-2025-62708 is considered a moderate severity vulnerability due to its potential for causing large memory usage.

2

How do I fix CVE-2025-62708?

To fix CVE-2025-62708, upgrade to pypdf version 6.1.3 or later.

3

What effect does CVE-2025-62708 have on PDF documents?

CVE-2025-62708 allows attackers to craft a malicious PDF that can lead to excessive memory consumption during content stream parsing.

4

Is CVE-2025-62708 present in earlier versions of pypdf?

Yes, CVE-2025-62708 affects all versions of pypdf prior to 6.1.3.

5

What type of attack can exploit CVE-2025-62708?

CVE-2025-62708 can be exploited through crafted PDF files that improperly leverage the LZWDecode filter.

Contact

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