CVE-2026-71852: CWE-834: Excessive Iteration in py-pdf pypdf
CVE-2026-71852 is a medium severity vulnerability in the pypdf library prior to version 6.15.0. It involves excessive iteration in the Font._collect_cid_character_widths function, which can cause long runtimes and high memory usage when processing crafted PDFs with unusually large CID font width ranges or excessive width entries. This issue is fixed in pypdf version 6.15.0.
AI Analysis
Technical Summary
The vulnerability CVE-2026-71852 affects the pypdf library, a pure-Python PDF processing tool. Before version 6.15.0, the function Font._collect_cid_character_widths in pypdf/_font.py can experience excessive iteration when handling crafted PDF files that contain unusually large CID font /W width ranges or excessive width entries during text extraction. This leads to long processing times and increased memory consumption. The issue is addressed and fixed in pypdf version 6.15.0.
Potential Impact
An attacker can craft a PDF that triggers excessive iteration and memory consumption in the vulnerable function, potentially causing denial of service due to resource exhaustion during text extraction. There is no indication of code execution or data corruption. The impact is limited to performance degradation and resource exhaustion on the client processing the PDF.
Mitigation Recommendations
Upgrade to pypdf version 6.15.0 or later, where this issue is fixed. No other mitigation or workaround is documented. Patch status is confirmed fixed in version 6.15.0.
CVE-2026-71852: CWE-834: Excessive Iteration in py-pdf pypdf
Description
CVE-2026-71852 is a medium severity vulnerability in the pypdf library prior to version 6.15.0. It involves excessive iteration in the Font._collect_cid_character_widths function, which can cause long runtimes and high memory usage when processing crafted PDFs with unusually large CID font width ranges or excessive width entries. This issue is fixed in pypdf version 6.15.0.
CVSS v4.0
Score 4.8medium
Affected software
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Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The vulnerability CVE-2026-71852 affects the pypdf library, a pure-Python PDF processing tool. Before version 6.15.0, the function Font._collect_cid_character_widths in pypdf/_font.py can experience excessive iteration when handling crafted PDF files that contain unusually large CID font /W width ranges or excessive width entries during text extraction. This leads to long processing times and increased memory consumption. The issue is addressed and fixed in pypdf version 6.15.0.
Potential Impact
An attacker can craft a PDF that triggers excessive iteration and memory consumption in the vulnerable function, potentially causing denial of service due to resource exhaustion during text extraction. There is no indication of code execution or data corruption. The impact is limited to performance degradation and resource exhaustion on the client processing the PDF.
Mitigation Recommendations
Upgrade to pypdf version 6.15.0 or later, where this issue is fixed. No other mitigation or workaround is documented. Patch status is confirmed fixed in version 6.15.0.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- GitHub_M
- Date Reserved
- 2026-08-07T18:26:53.523Z
- Cvss Version
- 4.0
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a772658bf8831d539846be1
Added to database: 08/08/2026, 12:51:36 UTC
Last enriched: 08/08/2026, 12:53:22 UTC
Last updated: 08/08/2026, 13:23:29 UTC
Views: 4
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