Infinite loop Affecting pypdf package, versions [,6.21.4)
Threat Intelligence
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
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Test your applications- Snyk IDSNYK-PYTHON-PYPDF-22132193
- published2 Nov 2026
- disclosed30 Oct 2026
- creditsmaeljaish771
Introduced: 30 Oct 2026
NewCVE-2026-119203 (opens in a new tab)How to fix?
Upgrade pypdf to version 6.21.4 or higher.
Overview
pypdf is an A pure-python PDF library capable of splitting, merging, cropping, and transforming PDF files
Affected versions of this package are vulnerable to Infinite loop via _read_standard_xref_table in pypdf/_reader.py, where a malformed PDF containing a standard cross-reference table that never reaches a trailer keyword causes the parser to seek back to the same stream position indefinitely, resulting in an infinite loop and a crash. An attacker can trigger this condition by supplying a PDF with a crafted or truncated xref section.