---
id: CVE-2026-71852
title: pypdf is a free and open-source pure-python PDF library
summary: >-
  pypdf is a free and open-source pure-python PDF library. Prior to 6.15.0, a
  crafted PDF can cause long runtimes and large memory consumption when
  pypdf/_font.py function Font._collect_cid_character_widths expands unusually
  large CID font…
severity: medium
cwe:
  - CWE-834
vendor: pypdf
product: pypdf
affected:
  - pypdf < 6.15.0
patched:
  - pypdf 6.15.0
published: '2026-08-07'
updated: '2026-09-10'
sourceUpdated: '2026-09-10T20:30:11.423'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-71852'
references:
  - url: >-
      https://github.com/py-pdf/pypdf/commit/51cb6acf9e8a35b77e90b4d87d28fe3e1416d7d7
    label: security-advisories@github.com
  - url: 'https://github.com/py-pdf/pypdf/pull/3946'
    label: security-advisories@github.com
  - url: 'https://github.com/py-pdf/pypdf/releases/tag/6.15.0'
    label: security-advisories@github.com
  - url: 'https://github.com/py-pdf/pypdf/security/advisories/GHSA-fwg2-594c-jp42'
    label: security-advisories@github.com
  - url: 'https://github.com/py-pdf/pypdf'
tags:
  - nvd
  - osv
  - pip
epss: 0.00127
epssPercentile: 0.02688
aliases:
  - GHSA-fwg2-594c-jp42
  - PYSEC-2026-3656
ecosystem: pip
ingestedAt: '2026-08-07T19:14:14.302Z'
---

## Overview

pypdf is a free and open-source pure-python PDF library. Prior to 6.15.0, a crafted PDF can cause long runtimes and large memory consumption when pypdf/_font.py function Font._collect_cid_character_widths expands unusually large CID font /W width ranges or excessive width entries during text extraction. This issue is fixed in 6.15.0.

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.

## Package advisory (CVE-2026-71852)

Affected packages:

- `pypdf < 6.15.0`

Patched in:

- `pypdf 6.15.0`

Source: https://osv.dev/vulnerability/GHSA-fwg2-594c-jp42