CVE-2026-102995: CWE-400: Uncontrolled Resource Consumption in py-pdf pypdf
CVE-2026-102995 is a high-severity vulnerability in the py-pdf pypdf library prior to version 6.18.1. It involves uncontrolled resource consumption caused by crafted PDF files containing large source-code or destination-string tokens in a font /ToUnicode mapping. This triggers excessive memory use during parsing in the pypdf/_cmap.py parse_bfchar function, particularly during text extraction operations. The issue is a follow-up to previous fixes for similar resource consumption problems and is resolved in pypdf version 6.18.1.
AI Analysis
Technical Summary
The vulnerability in pypdf versions before 6.18.1 allows a crafted PDF to embed unusually large tokens in the font /ToUnicode mapping. When pypdf processes these tokens in the parse_bfchar function, it decodes and retains oversized values, leading to excessive memory consumption. This uncontrolled resource consumption (CWE-400) can degrade system performance or cause denial of service during PDF text extraction. The flaw is limited to the token-length path and was addressed in version 6.18.1.
Potential Impact
Exploitation of this vulnerability can cause excessive memory consumption in applications using vulnerable pypdf versions when processing maliciously crafted PDFs. This may lead to denial of service or degraded performance due to resource exhaustion. There is no indication of code execution or data corruption. No known exploits are reported in the wild.
Mitigation Recommendations
This vulnerability is fixed in pypdf version 6.18.1. Users should upgrade to version 6.18.1 or later to remediate the issue. No additional mitigation steps are indicated.
CVE-2026-102995: CWE-400: Uncontrolled Resource Consumption in py-pdf pypdf
Description
CVE-2026-102995 is a high-severity vulnerability in the py-pdf pypdf library prior to version 6.18.1. It involves uncontrolled resource consumption caused by crafted PDF files containing large source-code or destination-string tokens in a font /ToUnicode mapping. This triggers excessive memory use during parsing in the pypdf/_cmap.py parse_bfchar function, particularly during text extraction operations. The issue is a follow-up to previous fixes for similar resource consumption problems and is resolved in pypdf 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 in pypdf versions before 6.18.1 allows a crafted PDF to embed unusually large tokens in the font /ToUnicode mapping. When pypdf processes these tokens in the parse_bfchar function, it decodes and retains oversized values, leading to excessive memory consumption. This uncontrolled resource consumption (CWE-400) can degrade system performance or cause denial of service during PDF text extraction. The flaw is limited to the token-length path and was addressed in version 6.18.1.
Potential Impact
Exploitation of this vulnerability can cause excessive memory consumption in applications using vulnerable pypdf versions when processing maliciously crafted PDFs. This may lead to denial of service or degraded performance due to resource exhaustion. There is no indication of code execution or data corruption. No known exploits are reported in the wild.
Mitigation Recommendations
This vulnerability is fixed in pypdf version 6.18.1. Users should upgrade to version 6.18.1 or later to remediate the issue. No additional mitigation steps are indicated.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- GitHub_M
- Date Reserved
- 2026-09-29T20:46:08.334Z
- Cvss Version
- 4.0
- State
- PUBLISHED
Threat ID: 6abd72532a4e24523d8ec0e1
Added to database: 09/30/2026, 20:34:27 UTC
Last enriched: 09/30/2026, 20:48:20 UTC
Last updated: 10/01/2026, 03:53:59 UTC
Views: 8
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