Volerion logoVolerion
Volerion logoVolerion

pypdf Array-Based Stream Processing Vulnerability Leading to Performance Degradation

Vulnerability

A vulnerability in pypdf, a pure-Python PDF library, exists in versions prior to 6.9.1. It allows an attacker to create a malicious PDF that causes excessive runtime and memory consumption. Exploitation requires the PDF to contain an array-based stream with a large number of entries.

Impact

Exploitation of this vulnerability results in inefficient processing of array-based streams, causing increased runtime and memory usage.

Remediation

Users can upgrade to pypdf version 6.9.1 or apply the changes from Pull Request #3686 if an immediate upgrade is not possible.

Added: Mar 20, 2026, 10:21 AM
Updated: Mar 20, 2026, 10:21 AM

Vulnerability Rating

Custom Algorithm
spread
5.4
impact
0.6
exploitability
4.2
remediation
7.7
relevance
4.2
threat
0.0
urgency
2.9
incentive
0.0

Our algorithm analyzes dozens of metrics to generate these 8 key vulnerability categories, which are then combined to calculate the overall risk score.