---
id: CVE-2026-103000
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 6.19.0, a
  crafted PDF can provide unusually large alphabetical page-label values that
  cause pypdf/_page_labels.py to generate strings beyond a reasonable page-label
  length…
severity: high
cvss: 8.7
cvssVector: 'CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N'
cwe:
  - CWE-400
vendor: py-pdf
product: pypdf
affected:
  - pypdf < 6.19.0
published: '2026-09-30'
updated: '2026-09-30'
sourceUpdated: '2026-09-30T21:17:07.490'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-103000'
references:
  - url: >-
      https://github.com/py-pdf/pypdf/commit/0d8b5a8832cde1ba308b5c27567b879b7b7eed4a
    label: security-advisories@github.com
  - url: 'https://github.com/py-pdf/pypdf/pull/4096'
    label: security-advisories@github.com
  - url: 'https://github.com/py-pdf/pypdf/releases/tag/6.19.0'
    label: security-advisories@github.com
  - url: 'https://github.com/py-pdf/pypdf/security/advisories/GHSA-w23x-9jrw-r45c'
    label: security-advisories@github.com
tags:
  - nvd
  - cve.org
ssvc:
  exploitation: none
  automatable: 'yes'
  technicalImpact: partial
  timestamp: '2026-09-30T20:49:14.062135Z'
cvssSource: cna
ingestedAt: '2026-09-30T21:25:07.840Z'
---

## Overview

pypdf is a free and open-source pure-python PDF library. Prior to 6.19.0, a crafted PDF can provide unusually large alphabetical page-label values that cause pypdf/_page_labels.py to generate strings beyond a reasonable page-label length when an application retrieves document page labels, consuming excessive memory and potentially making the application unavailable. This issue is fixed in version 6.19.0.

## Remediation

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