---
id: CVE-2026-59937
title: >-
  pypdf: pypdf: Denial of Service via crafted PDF with malformed cross-reference
  streams (CVE-2026-59937)
summary: >-
  A flaw was found in pypdf, a pure-python PDF library. A remote attacker could
  exploit this vulnerability by crafting a malicious PDF file containing
  repeated malformed cross-reference streams. This could cause the pypdf library
  to spend ex…
severity: medium
cvss: 6.5
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H'
cvssSource: vendor
cwe:
  - CWE-1050
  - CWE-400
vendor: Red Hat
product: Red Hat Enterprise Linux AI (RHEL AI) 3
affected:
  - exploit_intelligence
  - openshift_lightspeed
  - ansible_automation_platform 2
  - enterprise_linux_ai_rhel_ai 3
  - openshift_ai_rhoai
  - quay 3
patched:
  - pypdf 6.14.0
published: '2026-07-08'
updated: '2026-10-15'
sourceUpdated: '2026-10-15T11:20:43+00:00'
source: CSAF
sourceUrl: 'https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-59937.json'
references:
  - url: >-
      https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-59937.json
  - url: 'https://access.redhat.com/security/cve/CVE-2026-59937'
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2498170'
  - url: 'https://www.cve.org/CVERecord?id=CVE-2026-59937'
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2026-59937'
  - url: >-
      https://github.com/py-pdf/pypdf/commit/b5fc5aa714f4b696fb9b1deaa35a9e4a4eb50dae
  - url: 'https://github.com/py-pdf/pypdf/pull/3887'
  - url: 'https://github.com/py-pdf/pypdf/releases/tag/6.14.0'
  - url: 'https://github.com/py-pdf/pypdf/security/advisories/GHSA-55h5-xmcq-c37v'
  - url: 'https://github.com/py-pdf/pypdf'
  - url: 'https://github.com/advisories/GHSA-55h5-xmcq-c37v'
tags:
  - csaf
  - vex
  - red-hat
  - osv
  - pip
  - ghsa
epss: 0.0062
epssPercentile: 0.49483
aliases:
  - GHSA-55h5-xmcq-c37v
  - PYSEC-2026-3610
ecosystem: pip
ingestedAt: '2026-07-23T15:18:37.923Z'
---

## Overview

A flaw was found in pypdf, a pure-python PDF library. A remote attacker could exploit this vulnerability by crafting a malicious PDF file containing repeated malformed cross-reference streams. This could cause the pypdf library to spend excessive time recovering broken cross-reference table entries, leading to a denial of service (DoS) condition for applications processing such files.

## Vendor advisories

- **Red Hat VEX** · Moderate · affected: Exploit Intelligence, OpenShift Lightspeed, Red Hat Ansible Automation Platform 2, Red Hat Enterprise Linux AI (RHEL AI) 3, Red Hat OpenShift AI (RHOAI), Red Hat Quay 3 · no fix planned: Exploit Intelligence, OpenShift Lightspeed, Red Hat Ansible Automation Platform 2, Red Hat Enterprise Linux AI (RHEL AI) 3, … · updated 2026-10-15 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-59937.json)

**pypdf: pypdf: Denial of Service via crafted PDF with malformed cross-reference streams** — rated Moderate by Red Hat. Released 2026-07-08, updated 2026-10-15.

Affected:

- Exploit Intelligence
- OpenShift Lightspeed
- Red Hat Ansible Automation Platform 2
- Red Hat Enterprise Linux AI (RHEL AI) 3
- Red Hat OpenShift AI (RHOAI)
- Red Hat Quay 3

No fix planned:

- Exploit Intelligence
- OpenShift Lightspeed
- Red Hat Ansible Automation Platform 2
- Red Hat Enterprise Linux AI (RHEL AI) 3
- Red Hat OpenShift AI (RHOAI)
- Red Hat Quay 3

## Remediation

Fix deferred

## Package advisory (CVE-2026-59937)

Affected packages:

- `pypdf < 6.14.0`

Patched in:

- `pypdf 6.14.0`

Source: https://osv.dev/vulnerability/GHSA-55h5-xmcq-c37v