Pdfly: pypdf: Possible infinite loop when processing outlines/bookmarks in writer (CVE-2026-54531)
A vulnerability in pdfly's pypdf component allows an attacker to craft a PDF that causes an infinite loop when merging a file with outlines/bookmarks into a writer. This issue has been fixed in pypdf version 6.13.0. Users unable to upgrade immediately can apply the changes from the referenced pull request as a workaround.
AI Analysis
Technical Summary
The vulnerability identified as CVE-2026-54531 affects pdfly's pypdf library. It occurs when processing outlines or bookmarks during the merging of PDF files into a writer, leading to a possible infinite loop. This can be triggered by an attacker crafting a malicious PDF file. The issue has been addressed and fixed in pypdf version 6.13.0.
Potential Impact
An attacker can cause a denial of service condition by triggering an infinite loop in the PDF processing component, potentially impacting availability of the application using the vulnerable pypdf versions. No privilege escalation, code execution, or data disclosure is indicated.
Mitigation Recommendations
Upgrade to pypdf version 6.13.0 or later, where this vulnerability is fixed. If immediate upgrade is not possible, apply the changes from pull request #3830 as a temporary workaround.
Pdfly: pypdf: Possible infinite loop when processing outlines/bookmarks in writer (CVE-2026-54531)
Description
A vulnerability in pdfly's pypdf component allows an attacker to craft a PDF that causes an infinite loop when merging a file with outlines/bookmarks into a writer. This issue has been fixed in pypdf version 6.13.0. 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
The vulnerability identified as CVE-2026-54531 affects pdfly's pypdf library. It occurs when processing outlines or bookmarks during the merging of PDF files into a writer, leading to a possible infinite loop. This can be triggered by an attacker crafting a malicious PDF file. The issue has been addressed and fixed in pypdf version 6.13.0.
Potential Impact
An attacker can cause a denial of service condition by triggering an infinite loop in the PDF processing component, potentially impacting availability of the application using the vulnerable pypdf versions. No privilege escalation, code execution, or data disclosure is indicated.
Mitigation Recommendations
Upgrade to pypdf version 6.13.0 or later, where this vulnerability is fixed. If immediate upgrade is not possible, apply the changes from pull request #3830 as a temporary workaround.
Technical Details
- Gcve Source
- db.gcve.eu
- Osv Id
- BREW-pdfly-CVE-2026-54531
- Osv Schema Version
- 1.7.3
- Ecosystems
- ["Homebrew"]
- Cvss Version
- 4.0
- State
- PUBLISHED
Threat ID: 6ac1396ca43b0b3b89d5fdda
Added to database: 10/03/2026, 17:20:44 UTC
Last enriched: 10/03/2026, 17:26:09 UTC
Last updated: 10/04/2026, 02:46:05 UTC
Views: 5
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