---
id: "CVE-2026-113792"
kind: "vulnerability"
aliases: ["CVE-2026-113792", "GHSA-qfv9-64jg-mh7p"]
title: "pypdf: Possible infinite loop in PdfWriter.find_outline_item"
severity: "medium"
cvss: 6.0
epss: 0.004660000093281269
exploited: false
status: "open"
category: "package"
products: [{"name": "pypdf", "fixed": ["6.20.1"], "affected": "< 6.20.1", "ecosystem": "pypi"}]
ecosystems: ["pypi"]
tags: ["cwe-835", "package", "pdf-processing", "pypdf", "python"]
not_affected_if: ["does-not-call-find-outline-item", "no-untrusted-pdf-input", "pypdf-at-6.20.1-or-later"]
published_at: "2026-10-21T16:17:27+00:00"
first_seen_at: "2026-10-23T19:11:32+00:00"
updated_at: "2026-10-23T21:57:29+00:00"
sources: [{"source": "ghsa", "url": "https://github.com/advisories/GHSA-qfv9-64jg-mh7p", "first_seen_at": "2026-10-23T19:11:32+00:00"}, {"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-113792", "first_seen_at": "2026-10-23T21:57:29+00:00"}]
---

# pypdf: Possible infinite loop in PdfWriter.find_outline_item

pypdf's PdfWriter.find_outline_item can enter an infinite loop when given a crafted PDF, causing the process to hang. An attacker who can supply a PDF to code that calls this method can stall that process (denial of service).

_Summary, check and fix written by a model from the sources; labelled as such._

## Affected

- pypi:pypdf affected < 6.20.1 fixed 6.20.1

## How to check

Run pip show pypdf or check requirements/lockfiles for pypdf versions below 6.20.1.
Search code for calls to find_outline_item on a PdfWriter object.

## Fix

Upgrade pypdf to 6.20.1 or later.
If you cannot upgrade, apply the changes from PR #4188 in the pypdf repository.

## Timeline

- 2026-10-23T19:11:32+00:00 ghsa https://github.com/advisories/GHSA-qfv9-64jg-mh7p
- 2026-10-23T21:57:29+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-113792

## From the sources

### Impact

An attacker who uses this vulnerability can craft a PDF which leads to an infinite loop. This requires calling `find_outline_item` on a `PdfWriter`.

### Patches

This has been fixed in [pypdf==6.20.1](https://github.com/py-pdf/pypdf/releases/tag/6.20.1).

### Workarounds

If you cannot upgrade yet, consider applying the changes from PR [#4188](https://github.com/py-pdf/pypdf/pull/4188).

---

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