Resource exhaustion in Py-Pdf Pypdf
CVE-2025-55197
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.
Vulnerability class: DoS (Denial of Service)
Published · last modified .
CVSS v3 metric
CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.
EPSS exploit prediction
EPSS: 0.005 (37.3th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 37th percentile — 37.3% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.004 · newest: 0.005 · change: +0.000
Affected products
- Py-Pdf Pypdf — versions < 6.0.0
- Pypdf Project
Weakness classification (CWE)
Public proof-of-concept exploits
References
- github.com/py-pdf/pypdf/security/advisories/GHSA-7hfw-26vp-jp8m (Third Party Advisory, Mitigation)
- github.com/py-pdf/pypdf/issues/3429 (Issue Tracking)
- github.com/py-pdf/pypdf/pull/3430 (Patch)
- github.com/py-pdf/pypdf/blob/0dd57738bbdcdb63f0fb43d8a6b3d222b6946595/pypdf/fil… (Product)
- github.com/py-pdf/pypdf/releases/tag/6.0.0 (Release Notes)
Frequently asked questions
- What is CVE-2025-55197?
- CVE-2025-55197 is a high-severity vulnerability in Py-Pdf Pypdf, classified under Uncontrolled Resource Consumption. CVSS score: 7.5/10. Published 2025-08-13.
- How severe is CVE-2025-55197?
- High severity. CVSS v3 base score is 7.5 out of 10.
- Is CVE-2025-55197 known to be exploited?
- 1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.