CVE-2025-55197
pypdf's Manipulated FlateDecode streams can exhaust RAM
- State
- Published
- Severity
- 6.6 Medium
- Published
- Aug 13, 2025
- Updated
- Aug 14, 2025
- Reserved
- Aug 8, 2025
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.
Scores
| CVSS | Score | Vector | Source |
|---|---|---|---|
| 4.0 | 6.6 Medium | 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 | GitHub_M |
Weaknesses
Affected Products
| Product | Versions |
|---|---|
pypdfpy-pdf |
|
References
- https://github.com/py-pdf/pypdf/security/advisories/GHSA-7hfw-26vp-jp8m
- https://github.com/py-pdf/pypdf/issues/3429
- https://github.com/py-pdf/pypdf/pull/3430
- https://github.com/py-pdf/pypdf/blob/0dd57738bbdcdb63f0fb43d8a6b3d222b6946595/pypdf/filters.py#L72-L143
- https://github.com/py-pdf/pypdf/releases/tag/6.0.0
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