Pdfly: pypdf: Possible long runtimes/large memory usage when retrieving outlines (CVE-2026-84310)
A vulnerability in pdfly's pypdf component allows crafted PDF files with many or deeply nested outlines to cause long runtimes and high memory usage when outlines are accessed. This can degrade performance or cause denial of service conditions. The issue is fixed in pypdf version 6.16.1. Users unable to upgrade immediately can apply the changes from pull request #3966 as a workaround.
AI Analysis
Technical Summary
CVE-2026-84310 affects the pdfly product's pypdf library, where accessing PDF outlines with numerous entries or deeply nested outlines with repeated nesting paths can lead to excessive runtime and memory consumption. This vulnerability can be triggered by an attacker supplying a malicious PDF designed to exploit this behavior. The issue has been resolved in pypdf version 6.16.1.
Potential Impact
An attacker can craft a PDF that causes the application to consume excessive CPU time and memory when processing document outlines, potentially leading to denial of service or degraded performance. No direct code execution or data compromise is described.
Mitigation Recommendations
Upgrade to pypdf version 6.16.1 or later, where the vulnerability is fixed. If immediate upgrade is not possible, apply the changes from pull request #3966 as a temporary workaround.
Pdfly: pypdf: Possible long runtimes/large memory usage when retrieving outlines (CVE-2026-84310)
Description
A vulnerability in pdfly's pypdf component allows crafted PDF files with many or deeply nested outlines to cause long runtimes and high memory usage when outlines are accessed. This can degrade performance or cause denial of service conditions. The issue is fixed in pypdf version 6.16.1. Users unable to upgrade immediately can apply the changes from pull request #3966 as a workaround.
CVSS v4.0
Affected software
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AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-84310 affects the pdfly product's pypdf library, where accessing PDF outlines with numerous entries or deeply nested outlines with repeated nesting paths can lead to excessive runtime and memory consumption. This vulnerability can be triggered by an attacker supplying a malicious PDF designed to exploit this behavior. The issue has been resolved in pypdf version 6.16.1.
Potential Impact
An attacker can craft a PDF that causes the application to consume excessive CPU time and memory when processing document outlines, potentially leading to denial of service or degraded performance. No direct code execution or data compromise is described.
Mitigation Recommendations
Upgrade to pypdf version 6.16.1 or later, where the vulnerability is fixed. If immediate upgrade is not possible, apply the changes from pull request #3966 as a temporary workaround.
Technical Details
- Gcve Source
- db.gcve.eu
- Osv Id
- BREW-pdfly-CVE-2026-84310
- Osv Schema Version
- 1.7.3
- Ecosystems
- ["Homebrew"]
- Cvss Version
- 4.0
- State
- PUBLISHED
Threat ID: 6ac1396ca43b0b3b89d5fdd3
Added to database: 10/03/2026, 17:20:44 UTC
Last enriched: 10/03/2026, 17:25:41 UTC
Last updated: 10/04/2026, 02:46:07 UTC
Views: 2
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