CVE-2026-59937: CWE-400: Uncontrolled Resource Consumption in py-pdf pypdf
pypdf is a pure-Python PDF library vulnerable to uncontrolled resource consumption prior to version 6.14.0. An attacker can craft a PDF with repeated malformed cross-reference streams causing excessive runtime during recovery of broken cross-reference table entries. This vulnerability is identified as CWE-400 and has a CVSS 4.0 base score of 6.9 (medium severity). The issue is fixed in pypdf version 6.14.0.
AI Analysis
Technical Summary
CVE-2026-59937 describes a resource exhaustion vulnerability in pypdf before version 6.14.0. Specifically, an attacker can create a malicious PDF containing repeated malformed cross-reference streams. When pypdf processes such a file, it spends excessive time attempting to recover broken cross-reference table entries, leading to uncontrolled resource consumption. This can degrade performance or cause denial of service conditions. The vulnerability is resolved in pypdf 6.14.0.
Potential Impact
The vulnerability allows an unauthenticated attacker to cause pypdf to consume excessive CPU resources by processing specially crafted PDF files. This can result in denial of service or degraded performance of applications using vulnerable versions of pypdf. There is no indication of data disclosure or code execution. No known exploits are reported in the wild.
Mitigation Recommendations
This issue is fixed in pypdf version 6.14.0. Users should upgrade to version 6.14.0 or later to remediate this vulnerability. Patch status is confirmed by the vendor advisory stating the fix is included in 6.14.0. No additional mitigations are specified.
CVE-2026-59937: CWE-400: Uncontrolled Resource Consumption in py-pdf pypdf
Description
pypdf is a pure-Python PDF library vulnerable to uncontrolled resource consumption prior to version 6.14.0. An attacker can craft a PDF with repeated malformed cross-reference streams causing excessive runtime during recovery of broken cross-reference table entries. This vulnerability is identified as CWE-400 and has a CVSS 4.0 base score of 6.9 (medium severity). The issue is fixed in pypdf version 6.14.0.
CVSS v4.0
Score 6.9medium
Affected software
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Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-59937 describes a resource exhaustion vulnerability in pypdf before version 6.14.0. Specifically, an attacker can create a malicious PDF containing repeated malformed cross-reference streams. When pypdf processes such a file, it spends excessive time attempting to recover broken cross-reference table entries, leading to uncontrolled resource consumption. This can degrade performance or cause denial of service conditions. The vulnerability is resolved in pypdf 6.14.0.
Potential Impact
The vulnerability allows an unauthenticated attacker to cause pypdf to consume excessive CPU resources by processing specially crafted PDF files. This can result in denial of service or degraded performance of applications using vulnerable versions of pypdf. There is no indication of data disclosure or code execution. No known exploits are reported in the wild.
Mitigation Recommendations
This issue is fixed in pypdf version 6.14.0. Users should upgrade to version 6.14.0 or later to remediate this vulnerability. Patch status is confirmed by the vendor advisory stating the fix is included in 6.14.0. No additional mitigations are specified.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- GitHub_M
- Date Reserved
- 2026-07-07T18:20:06.127Z
- Cvss Version
- 4.0
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a4e88dcc9d9e3dbe37f6518
Added to database: 07/08/2026, 17:29:00 UTC
Last enriched: 07/08/2026, 17:43:20 UTC
Last updated: 07/08/2026, 17:59:26 UTC
Views: 4
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