CVE-2026-102996: CWE-400: Uncontrolled Resource Consumption in py-pdf pypdf
pypdf is a free and open-source pure-python PDF library. Prior to 6.18.1, a crafted PDF can provide a TrueType or Type1 simple font with an unusually large /Widths array, causing pypdf/_font.py Font._collect_tt_t1_character_widths to process entries beyond the 256 character codes meaningful for a simple font and consume excessive memory during operations such as text extraction. This issue is fixed in version 6.18.1.
AI Analysis
Technical Summary
The vulnerability exists in pypdf, a pure-Python PDF library, where a crafted PDF can specify a TrueType or Type1 simple font with an excessively large /Widths array. The function Font._collect_tt_t1_character_widths processes more entries than the 256 character codes meaningful for a simple font, resulting in excessive memory consumption. This flaw can be triggered during operations such as text extraction. The issue is resolved in pypdf version 6.18.1.
Potential Impact
An attacker can cause pypdf to consume excessive memory by providing a crafted PDF with a large /Widths array in a simple font. This may lead to denial of service or application instability during PDF processing tasks like text extraction. There is no indication of privilege escalation or code execution.
Mitigation Recommendations
Upgrade pypdf to version 6.18.1 or later, where this vulnerability is fixed. No other mitigation is required as the issue is resolved in the official patch.
CVE-2026-102996: CWE-400: Uncontrolled Resource Consumption in py-pdf pypdf
Description
pypdf is a free and open-source pure-python PDF library. Prior to 6.18.1, a crafted PDF can provide a TrueType or Type1 simple font with an unusually large /Widths array, causing pypdf/_font.py Font._collect_tt_t1_character_widths to process entries beyond the 256 character codes meaningful for a simple font and consume excessive memory during operations such as text extraction. This issue is fixed in version 6.18.1.
CVSS v4.0
Score 8.7high
Affected software
py-pdf
pypdf
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Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The vulnerability exists in pypdf, a pure-Python PDF library, where a crafted PDF can specify a TrueType or Type1 simple font with an excessively large /Widths array. The function Font._collect_tt_t1_character_widths processes more entries than the 256 character codes meaningful for a simple font, resulting in excessive memory consumption. This flaw can be triggered during operations such as text extraction. The issue is resolved in pypdf version 6.18.1.
Potential Impact
An attacker can cause pypdf to consume excessive memory by providing a crafted PDF with a large /Widths array in a simple font. This may lead to denial of service or application instability during PDF processing tasks like text extraction. There is no indication of privilege escalation or code execution.
Mitigation Recommendations
Upgrade pypdf to version 6.18.1 or later, where this vulnerability is fixed. No other mitigation is required as the issue is resolved in the official patch.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- GitHub_M
- Date Reserved
- 2026-09-29T20:46:08.335Z
- Cvss Version
- 4.0
- State
- PUBLISHED
Threat ID: 6abd72532a4e24523d8ec0e2
Added to database: 09/30/2026, 20:34:27 UTC
Last enriched: 09/30/2026, 20:48:15 UTC
Last updated: 10/01/2026, 04:54:01 UTC
Views: 11
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