CVE-2026-24688

MEDIUM

pypdf < 6.6.2 - Denial of Service via Infinite Loop in Outline Processing

Title source: llm
STIX 2.1

Exploitation Summary

EIP tracks 1 public exploit for CVE-2026-24688. PoCs published by JoakimBulow.

AI-analyzed exploit summary This repository contains a working proof-of-concept for CVE-2026-24688, a critical Denial of Service (DoS) vulnerability in pypdf's outline parsing logic. The exploit demonstrates how circular references in PDF outlines cause an infinite loop, leading to system-wide crashes due to uncontrolled memory allocation.

Description

pypdf is a free and open-source pure-python PDF library. An attacker who uses an infinite loop vulnerability that is present in versions prior to 6.6.2 can craft a PDF which leads to an infinite loop. This requires accessing the outlines/bookmarks. This has been fixed in pypdf 6.6.2. If projects cannot upgrade yet, consider applying the changes from PR #3610 manually.

Exploits (1)

nomisec WORKING POC
by JoakimBulow · poc
https://github.com/JoakimBulow/CVE-2026-24688

This repository contains a working proof-of-concept for CVE-2026-24688, a critical Denial of Service (DoS) vulnerability in pypdf's outline parsing logic. The exploit demonstrates how circular references in PDF outlines cause an infinite loop, leading to system-wide crashes due to uncontrolled memory allocation.

Classification
Working Poc 100%
Attack Type
Dos
Complexity
Trivial
Reliability
Reliable
Target: pypdf version 6.6.0
No auth needed
Prerequisites: Python environment with pypdf==6.6.0 installed
devstral-2 · analyzed Feb 16, 2026 Full analysis →

References (4)

Core 4

Scores

CVSS v3 4.3
EPSS 0.0001
EPSS Percentile 2.9%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:L

CISA SSVC

Vulnrichment
Exploitation none
Automatable no
Technical Impact partial

Details

CWE
CWE-835
Status published
Products (2)
pypdf_project/pypdf < 6.6.2
pypi/pypdf 0 - 6.6.2PyPI
Published Jan 27, 2026
Tracked Since Feb 18, 2026