CVE-2026-31826
Received Received - Intake
Memory Exhaustion Vulnerability in pypdf Content Stream Parsing

Publication date: 2026-03-10

Last updated on: 2026-03-17

Assigner: GitHub, Inc.

Description
pypdf is a free and open-source pure-python PDF library. Prior to 6.8.0, an attacker who uses this vulnerability can craft a PDF which leads to large memory usage. This requires parsing a content stream with a rather large /Length value, regardless of the actual data length inside the stream. This vulnerability is fixed in 6.8.0.
CVSS Scores
EPSS Scores
Probability:
Percentile:
Meta Information
Published
2026-03-10
Last Modified
2026-03-17
Generated
2026-06-16
AI Q&A
2026-03-11
EPSS Evaluated
2026-06-15
NVD
CVE-2026-31826
EUVD
EUVD-2026-10924
Affected Vendors & Products
Showing 1 associated CPE
Vendor Product Version / Range
pypdf_project pypdf to 6.8.0 (exc)
Helpful Resources
Exploitability
CWE
CWE Icon
KEV
KEV Icon
CWE ID Description
CWE-770 The product allocates a reusable resource or group of resources on behalf of an actor without imposing any intended restrictions on the size or number of resources that can be allocated.
Attack-Flow Graph
AI Quick Actions
Instant insights powered by AI
Executive Summary

This vulnerability exists in the pypdf library, a pure-python PDF library. Before version 6.8.0, an attacker could craft a specially designed PDF file that causes the library to use a large amount of memory. This happens because the library parses a content stream with a very large /Length value, even if the actual data inside the stream is much smaller.

Impact Analysis

The impact of this vulnerability is high memory usage when processing maliciously crafted PDF files. This could lead to denial of service conditions by exhausting system memory resources, potentially causing the application using pypdf to crash or become unresponsive.

Compliance Impact

I don't know

Detection Guidance

I don't know

Mitigation Strategies

To mitigate this vulnerability, you should upgrade the pypdf library to version 6.8.0 or later, where the issue has been fixed.

Chat Assistant
Ask questions about this CVE
Hi! I’m here to help you understand CVE-2026-31826. Ask me anything about the vulnerability, its impact, or mitigation strategies.
0/70
EPSS Chart