CVE-2026-54651: CWE-835: Loop with Unreachable Exit Condition ('Infinite Loop') in py-pdf pypdf
A vulnerability in the pypdf library prior to version 6.13.1 allows an attacker to craft a specially designed PDF that causes an infinite loop when merging a file containing threads or articles. This issue is fixed in version 6.13.1.
AI Analysis
Technical Summary
CVE-2026-54651 is a CWE-835 (Loop with Unreachable Exit Condition) vulnerability in the pypdf Python library. An attacker can exploit this by crafting a malicious PDF that triggers an infinite loop during the merge operation involving files with threads or articles. This flaw exists in all versions before 6.13.1 and has been resolved in 6.13.1.
Potential Impact
The vulnerability can cause a denial of service condition by making the application enter an infinite loop, potentially leading to resource exhaustion or application unresponsiveness. There is no indication of privilege escalation, data disclosure, or code execution from the provided data.
Mitigation Recommendations
Upgrade to pypdf version 6.13.1 or later, where this infinite loop vulnerability is fixed. No other mitigation steps are indicated or required.
CVE-2026-54651: CWE-835: Loop with Unreachable Exit Condition ('Infinite Loop') in py-pdf pypdf
Description
A vulnerability in the pypdf library prior to version 6.13.1 allows an attacker to craft a specially designed PDF that causes an infinite loop when merging a file containing threads or articles. This issue is fixed in version 6.13.1.
CVSS v4.0
Score 6.9medium
Affected software
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Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-54651 is a CWE-835 (Loop with Unreachable Exit Condition) vulnerability in the pypdf Python library. An attacker can exploit this by crafting a malicious PDF that triggers an infinite loop during the merge operation involving files with threads or articles. This flaw exists in all versions before 6.13.1 and has been resolved in 6.13.1.
Potential Impact
The vulnerability can cause a denial of service condition by making the application enter an infinite loop, potentially leading to resource exhaustion or application unresponsiveness. There is no indication of privilege escalation, data disclosure, or code execution from the provided data.
Mitigation Recommendations
Upgrade to pypdf version 6.13.1 or later, where this infinite loop vulnerability is fixed. No other mitigation steps are indicated or required.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- GitHub_M
- Date Reserved
- 2026-06-15T20:16:46.198Z
- Cvss Version
- 4.0
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a39a0f6eed863c81e6b0291
Added to database: 06/22/2026, 20:54:14 UTC
Last enriched: 06/22/2026, 21:09:21 UTC
Last updated: 06/23/2026, 01:50:40 UTC
Views: 10
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