Pdfly: pypdf: Possible long runtimes/large memory usage for large CID font width ranges (CVE-2026-71852)
A vulnerability in pdfly's pypdf component allows crafted PDFs with large CID font width ranges to cause long runtimes and high memory usage during parsing, such as text extraction. This issue has been fixed in pypdf version 6.15.0. Users unable to upgrade immediately can apply the changes from the referenced pull request as a workaround.
AI Analysis
Technical Summary
CVE-2026-71852 describes a resource exhaustion vulnerability in pdfly's pypdf library where parsing font width entries with unusually large values in CID fonts can lead to prolonged runtimes and excessive memory consumption. This occurs during operations like text extraction. The vulnerability affects versions from 0.4.0 up to but not including 0.5.1_24. The issue has been addressed and fixed in pypdf version 6.15.0.
Potential Impact
An attacker can craft a malicious PDF that triggers long processing times and large memory usage in affected versions of pypdf, potentially leading to denial of service conditions or degraded performance during PDF parsing operations.
Mitigation Recommendations
Upgrade to pypdf version 6.15.0 or later to apply the official fix. If immediate upgrade is not possible, apply the changes from pull request #3946 as a temporary workaround.
Pdfly: pypdf: Possible long runtimes/large memory usage for large CID font width ranges (CVE-2026-71852)
Description
A vulnerability in pdfly's pypdf component allows crafted PDFs with large CID font width ranges to cause long runtimes and high memory usage during parsing, such as text extraction. This issue has been fixed in pypdf version 6.15.0. Users unable to upgrade immediately can apply the changes from the referenced pull request as a workaround.
CVSS v4.0
Affected software
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AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-71852 describes a resource exhaustion vulnerability in pdfly's pypdf library where parsing font width entries with unusually large values in CID fonts can lead to prolonged runtimes and excessive memory consumption. This occurs during operations like text extraction. The vulnerability affects versions from 0.4.0 up to but not including 0.5.1_24. The issue has been addressed and fixed in pypdf version 6.15.0.
Potential Impact
An attacker can craft a malicious PDF that triggers long processing times and large memory usage in affected versions of pypdf, potentially leading to denial of service conditions or degraded performance during PDF parsing operations.
Mitigation Recommendations
Upgrade to pypdf version 6.15.0 or later to apply the official fix. If immediate upgrade is not possible, apply the changes from pull request #3946 as a temporary workaround.
Technical Details
- Gcve Source
- db.gcve.eu
- Osv Id
- BREW-pdfly-CVE-2026-71852
- Osv Schema Version
- 1.7.3
- Ecosystems
- ["Homebrew"]
- Cvss Version
- 4.0
- State
- PUBLISHED
Threat ID: 6ac1396ca43b0b3b89d5fdd7
Added to database: 10/03/2026, 17:20:44 UTC
Last enriched: 10/03/2026, 17:25:56 UTC
Last updated: 10/04/2026, 03:10:23 UTC
Views: 5
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