Infinite loop Affecting pillow package, versions [5.1.0,13.0.0)
Threat Intelligence
Snyk has a proof-of-concept or detailed explanation of how to exploit this vulnerability.
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-PILLOW-21277785
- published20 Oct 2026
- disclosed19 Oct 2026
- creditUnknown
Introduced: 19 Oct 2026
NewCVE-2026-112406 (opens in a new tab)How to fix?
Upgrade pillow to version 13.0.0 or higher.
Overview
Affected versions of this package are vulnerable to Infinite loop via PdfParser.rewrite_pages() in src/PIL/PdfParser.py when processing a PDF file whose /Parent chain contains a cycle. The function walks the /Parent chain of every pre-existing page upward, stopping only when it reaches a node with no /Parent entry, so a cyclic reference causes the loop to run indefinitely. An attacker who controls the bytes of a PDF passed to the append path can trigger this condition, crashing the process.