CVE-2025-55197 - CVE House
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Status published Medium CVE-2025-55197

pypdf's Manipulated FlateDecode streams can exhaust RAM

Vulnerability 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.

Impact Analysis

Refer to official advisory for detailed impact metrics.

Remediation

Ensure systems are updated to the latest vendor-supplied patch levels.

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Credits & Attribution

No credits recorded in the NVD database.

References

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Affected Vendor

Affected Software

pypdf
Vulnerable Versions:
< 6.0.0

Timeline

Official Publish: August 13th, 2025
Last Modified: August 14th, 2025
Added to House: July 22nd, 2026

CVSS Vectors

Weaknesses (CWE)

CWE-400 CWE-770

MITRE ATT&CK TTPs

T1499 Endpoint Denial of Service
Impact
T1498 Network Denial of Service
Impact
T1190 Exploit Public-Facing Application
Initial Access
T1562 Impair Defenses
Defense Evasion
T1046 Network Service Discovery
Discovery