Allocation of Resources Without Limits or Throttling Affecting pypdf package, versions [,6.21.0)
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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- published22 Oct 2026
- disclosed21 Oct 2026
- creditAdrian Korwel
Introduced: 21 Oct 2026
NewCVE-2026-113789 (opens in a new tab)How to fix?
Upgrade pypdf to version 6.21.0 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 Allocation of Resources Without Limits or Throttling via the get_fields function in pypdf/_doc_common.py, which previously used a list for cycle detection instead of a set of object IDs, and imposed no limits on field count or depth. An attacker can supply a PDF with a deeply nested or excessively large AcroForm field tree to cause unbounded processing, crashing the application.