CVE-2026-71870: CWE-400: Uncontrolled Resource Consumption in py-pdf pypdf
pypdf is a free and open-source pure-python PDF library. Prior to 6.15.0, a crafted PDF can cause large memory consumption when pypdf/_cmap.py function parse_bfrange parses unusually large source-code or destination-string tokens in a font /ToUnicode CMap during text extraction. This issue is fixed in 6.15.0.
AI Analysis
Technical Summary
The pypdf library, a pure-python PDF processing tool, contains a vulnerability (CWE-400) related to uncontrolled resource consumption. Specifically, in versions before 6.15.0, the parse_bfrange function in pypdf/_cmap.py can consume excessive memory when processing crafted PDF files with unusually large source-code or destination-string tokens in font /ToUnicode CMaps during text extraction. This flaw can cause large memory consumption, potentially impacting application stability or availability. The vulnerability has been addressed and fixed in pypdf version 6.15.0.
Potential Impact
An attacker can craft a PDF file that triggers excessive memory consumption in affected versions of pypdf when text extraction is performed. This may lead to denial of service conditions due to resource exhaustion. There is no indication of privilege escalation, code execution, or data disclosure. No known exploits are reported in the wild.
Mitigation Recommendations
Upgrade to pypdf version 6.15.0 or later, where this vulnerability is fixed. No other mitigation or workaround is documented. Patch status is confirmed fixed in 6.15.0.
CVE-2026-71870: CWE-400: Uncontrolled Resource Consumption in py-pdf pypdf
Description
pypdf is a free and open-source pure-python PDF library. Prior to 6.15.0, a crafted PDF can cause large memory consumption when pypdf/_cmap.py function parse_bfrange parses unusually large source-code or destination-string tokens in a font /ToUnicode CMap during text extraction. This issue is fixed in 6.15.0.
CVSS v4.0
Score 4.8medium
Affected software
py-pdf
pypdf
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Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The pypdf library, a pure-python PDF processing tool, contains a vulnerability (CWE-400) related to uncontrolled resource consumption. Specifically, in versions before 6.15.0, the parse_bfrange function in pypdf/_cmap.py can consume excessive memory when processing crafted PDF files with unusually large source-code or destination-string tokens in font /ToUnicode CMaps during text extraction. This flaw can cause large memory consumption, potentially impacting application stability or availability. The vulnerability has been addressed and fixed in pypdf version 6.15.0.
Potential Impact
An attacker can craft a PDF file that triggers excessive memory consumption in affected versions of pypdf when text extraction is performed. This may lead to denial of service conditions due to resource exhaustion. There is no indication of privilege escalation, code execution, or data disclosure. No known exploits are reported in the wild.
Mitigation Recommendations
Upgrade to pypdf version 6.15.0 or later, where this vulnerability is fixed. No other mitigation or workaround is documented. Patch status is confirmed fixed in 6.15.0.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- GitHub_M
- Date Reserved
- 2026-08-07T18:26:53.524Z
- Cvss Version
- 4.0
- State
- PUBLISHED
Threat ID: 6a76350bbf8831d5390b01b3
Added to database: 08/07/2026, 19:42:03 UTC
Last enriched: 08/15/2026, 15:35:00 UTC
Last updated: 09/21/2026, 22:01:37 UTC
Views: 64
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