CVE-2026-113791: CWE-400: Uncontrolled Resource Consumption in py-pdf pypdf
Description
CVE-2026-113791 is a medium severity vulnerability in the py-pdf pypdf library prior to version 6.21.0. It involves uncontrolled resource consumption where an attacker can craft a PDF with many small operations in a content stream, causing excessive memory usage during parsing. This issue has been fixed in version 6.21.0.
CVSS v4.0
Score 6.0medium
Affected software
py-pdf
pypdf
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AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The vulnerability CVE-2026-113791 affects the py-pdf pypdf library versions before 6.21.0. An attacker can create a specially crafted PDF containing a content stream with numerous small operations. When pypdf parses this content stream, it consumes large amounts of memory, leading to uncontrolled resource consumption (CWE-400). This can degrade service or cause denial of service conditions. The issue is resolved in version 6.21.0.
Potential Impact
An attacker can cause excessive memory consumption during PDF parsing by supplying a maliciously crafted PDF file. This can lead to denial of service or degraded performance in applications using vulnerable versions of pypdf. There are no known exploits in the wild at this time.
Mitigation Recommendations
Upgrade to pypdf version 6.21.0 or later, where this vulnerability has been fixed. No other mitigations are indicated by the vendor advisory.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- GitHub_M
- Date Reserved
- 2026-10-20T17:39:41.373Z
- Cvss Version
- 4.0
- State
- PUBLISHED
Threat ID: 6ad8e1cc4d27ba8daabfb4f1
Added to database: 10/21/2026, 16:01:16 UTC
Last enriched: 10/21/2026, 16:15:31 UTC
Last updated: 10/21/2026, 16:16:22 UTC
Views: 5
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