pypdf is a free and open-source pure-python PDF library. Prior to version 6.0.0, an attacker can craft a PDF which leads to the RAM being exhausted. This requires just reading the file if a series of FlateDecode filters is used on a malicious cross-reference stream. Other content streams are affected on explicit access. This issue has been fixed in 6.0.0. If an update is not possible, a workaround involves including the fixed code from pypdf.filters.decompress into the existing filters file.

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

Attack Vector Network

Attack Complexity Low

Privileges Required None

Scope Unchanged

Confidentiality Impact None

Integrity Impact None

Availability Impact High

User Interaction None

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

The EPSS score is 0.00095.

Exploitation none

Automatable yes

Technical Impact partial

Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).

Vendor Product Default status Versions
py-pdf pypdf affected
Version Status Constraints
< 6.0.0 affected
—

Configuration 1 [-]

cpe:2.3:a:pypdf_project:pypdf:*:*:*:*:*:*:*:*

No data.

No data.

Subscriptions

Vendors Products
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Tracking

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Advisories
Source ID Title
EUVD EUVD EUVD-2025-24648 PyPDF's Manipulated FlateDecode streams can exhaust RAM
Github GHSA Github GHSA GHSA-7hfw-26vp-jp8m PyPDF's Manipulated FlateDecode streams can exhaust RAM
Fixes

Solution

No solution given by the vendor.

Workaround

No workaround given by the vendor.

References
Link Providers
https://github.com/py-pdf/pypdf/blob/0dd57738bbdcdb63f0fb43d8a6b3d222b6946595/pypdf/filters.py#L72-L143 cve-icon cve-icon cve-icon
https://github.com/py-pdf/pypdf/issues/3429 cve-icon cve-icon cve-icon
https://github.com/py-pdf/pypdf/pull/3430 cve-icon cve-icon cve-icon
https://github.com/py-pdf/pypdf/releases/tag/6.0.0 cve-icon cve-icon cve-icon
https://github.com/py-pdf/pypdf/security/advisories/GHSA-7hfw-26vp-jp8m cve-icon cve-icon cve-icon
https://nvd.nist.gov/vuln/detail/CVE-2025-55197 cve-icon
https://www.cve.org/CVERecord?id=CVE-2025-55197 cve-icon
History

Fri, 15 Aug 2025 20:15:00 +0000

Type Values Removed Values Added
First Time appeared Pypdf Project
Pypdf Project pypdf
CPEs cpe:2.3:a:pypdf_project:pypdf:*:*:*:*:*:*:*:*
Vendors & Products Pypdf Project
Pypdf Project pypdf
Metrics cvssV3_1

{'score': 6.5, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H'}

 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'}

Thu, 14 Aug 2025 15:15:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Thu, 14 Aug 2025 12:15:00 +0000

Type Values Removed Values Added
References
Metrics threat_severity

None

 cvssV3_1

{'score': 6.5, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H'}

threat_severity

Moderate

Wed, 13 Aug 2025 23:15:00 +0000

Type Values Removed Values Added
Description pypdf is a free and open-source pure-python PDF library. Prior to version 6.0.0, an attacker can craft a PDF which leads to the RAM being exhausted. This requires just reading the file if a series of FlateDecode filters is used on a malicious cross-reference stream. Other content streams are affected on explicit access. This issue has been fixed in 6.0.0. If an update is not possible, a workaround involves including the fixed code from pypdf.filters.decompress into the existing filters file.
Title pypdf's Manipulated FlateDecode streams can exhaust RAM
Weaknesses CWE-400
CWE-770
References
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'}
cve-icon MITRE

Status: PUBLISHED

Assigner: GitHub_M

Published:

Updated: 2025-08-14T14:50:48.663Z

Reserved: 2025-08-08T21:55:07.964Z

Link: CVE-2025-55197

cve-icon Vulnrichment

Updated: 2025-08-14T13:41:30.430Z

cve-icon NVD

Status : Analyzed

Published: 2025-08-13T23:15:27.660

Modified: 2025-08-15T20:05:20.427

Link: CVE-2025-55197

cve-icon Redhat

Severity : Moderate

Publid Date: 2025-08-13T23:03:02Z

Links: CVE-2025-55197 - Bugzilla

cve-icon OpenCVE Enrichment

No data.

Weaknesses