---
id: CVE-2026-24688
aliases:
  - GHSA-2q4j-m29v-hq73
  - PYSEC-2026-1827
title: pypdf has possible Infinite Loop when processing outlines/bookmarks
summary: pypdf has possible Infinite Loop when processing outlines/bookmarks
severity: medium
vendor: pypdf
product: pypdf
ecosystem: pip
affected:
  - pypdf < 6.6.2
patched:
  - pypdf 6.6.2
published: '2026-01-26'
updated: '2026-09-10'
sourceUpdated: '2026-09-10T03:50:32.300137224Z'
source: OSV
sourceUrl: 'https://osv.dev/vulnerability/GHSA-2q4j-m29v-hq73'
references:
  - url: 'https://github.com/py-pdf/pypdf/security/advisories/GHSA-2q4j-m29v-hq73'
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2026-24688'
  - url: 'https://github.com/py-pdf/pypdf/pull/3610'
  - url: >-
      https://github.com/py-pdf/pypdf/commit/b1282f8dcdc1a7b41ceab6740ffddfdf31b1fec1
  - url: 'https://github.com/py-pdf/pypdf'
  - url: 'https://github.com/py-pdf/pypdf/releases/tag/6.6.2'
tags:
  - osv
  - pip
  - exploit-available
epss: 0.00451
epssPercentile: 0.36595
exploits:
  github: 2
  githubRepos:
    - 'https://github.com/JoakimBulow/CVE-2026-24688'
    - 'https://github.com/Fomovet/cve-2026-24688'
  checkedAt: '2026-09-26T09:05:40.568Z'
exploitAvailable: true
ingestedAt: '2026-07-08T18:25:44.592Z'
---

## Overview

### Impact

An attacker who uses this vulnerability can craft a PDF which leads to an infinite loop. This requires accessing the outlines/bookmarks.

### Patches

This has been fixed in [pypdf 6.6.2](https://github.com/py-pdf/pypdf/releases/tag/6.6.2).

### Workarounds

If projects cannot upgrade yet, consider applying the changes from PR [#3610](https://github.com/py-pdf/pypdf/pull/3610).

## Affected packages

- `pypdf < 6.6.2`

## Remediation

Upgrade to a patched release:

- `pypdf 6.6.2`