CVE-2026-59937: CWE-400: Uncontrolled Resource Consumption in py-pdf pypdf
pypdf is a free and open-source pure-python PDF library. Prior to 6.14.0, an attacker can craft a PDF with repeated malformed cross-reference streams that cause pypdf to spend long runtimes recovering broken cross-reference table entries. This issue is fixed in version 6.14.0.
AI Analysis
Technical Summary
CVE-2026-59937 is an uncontrolled resource consumption vulnerability (CWE-400) in the pypdf library before version 6.14.0. An attacker can create a malicious PDF containing repeated malformed cross-reference streams, which triggers prolonged processing times during the recovery of broken cross-reference table entries. This can lead to denial of service by exhausting processing resources. The vulnerability is resolved in pypdf version 6.14.0.
Potential Impact
An attacker can cause pypdf to consume excessive processing time and resources by submitting specially crafted PDFs with malformed cross-reference streams. This may result in denial of service conditions where legitimate processing is delayed or interrupted. There is no indication of privilege escalation, data disclosure, or code execution from the provided data.
Mitigation Recommendations
Upgrade pypdf to version 6.14.0 or later, where this vulnerability has been fixed. No other mitigation or temporary workaround is indicated.
CVE-2026-59937: CWE-400: Uncontrolled Resource Consumption in py-pdf pypdf
Description
pypdf is a free and open-source pure-python PDF library. Prior to 6.14.0, an attacker can craft a PDF with repeated malformed cross-reference streams that cause pypdf to spend long runtimes recovering broken cross-reference table entries. This issue is fixed in 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 is an uncontrolled resource consumption vulnerability (CWE-400) in the pypdf library before version 6.14.0. An attacker can create a malicious PDF containing repeated malformed cross-reference streams, which triggers prolonged processing times during the recovery of broken cross-reference table entries. This can lead to denial of service by exhausting processing resources. The vulnerability is resolved in pypdf version 6.14.0.
Potential Impact
An attacker can cause pypdf to consume excessive processing time and resources by submitting specially crafted PDFs with malformed cross-reference streams. This may result in denial of service conditions where legitimate processing is delayed or interrupted. There is no indication of privilege escalation, data disclosure, or code execution from the provided data.
Mitigation Recommendations
Upgrade pypdf to version 6.14.0 or later, where this vulnerability has been fixed. No other mitigation or temporary workaround is indicated.
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: 07/16/2026, 10:07:26 UTC
Last updated: 08/22/2026, 10:52:10 UTC
Views: 93
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