Pdfly: pypdf: Possible large memory usage when retrieving alphabetical page labels (CVE-2026-103000)
A vulnerability in pdfly's pypdf component allows an attacker to craft a PDF that causes large memory consumption when retrieving alphabetical page labels. This issue affects versions from 0.4.0 up to but not including 0.5.1_26. The vulnerability has been fixed in pypdf version 6.19.0. Users unable to upgrade immediately can apply the changes from the referenced pull request as a workaround.
AI Analysis
Technical Summary
CVE-2026-103000 describes a vulnerability in pdfly's pypdf library where accessing page labels with large alphabetical values can lead to excessive memory usage. This can be triggered by a maliciously crafted PDF document. The issue affects versions >=0.4.0 and <0.5.1_26 and has been addressed in pypdf version 6.19.0. A workaround is available by applying the changes from pull request #4096.
Potential Impact
An attacker can cause large memory consumption on systems processing crafted PDF documents with large alphabetical page labels. This may lead to denial of service or resource exhaustion but does not indicate code execution or data compromise.
Mitigation Recommendations
Upgrade to pypdf version 6.19.0 where the vulnerability is fixed. If immediate upgrade is not possible, apply the changes from pull request #4096 as a temporary workaround.
Pdfly: pypdf: Possible large memory usage when retrieving alphabetical page labels (CVE-2026-103000)
Description
A vulnerability in pdfly's pypdf component allows an attacker to craft a PDF that causes large memory consumption when retrieving alphabetical page labels. This issue affects versions from 0.4.0 up to but not including 0.5.1_26. The vulnerability has been fixed in pypdf version 6.19.0. 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-2026-103000 describes a vulnerability in pdfly's pypdf library where accessing page labels with large alphabetical values can lead to excessive memory usage. This can be triggered by a maliciously crafted PDF document. The issue affects versions >=0.4.0 and <0.5.1_26 and has been addressed in pypdf version 6.19.0. A workaround is available by applying the changes from pull request #4096.
Potential Impact
An attacker can cause large memory consumption on systems processing crafted PDF documents with large alphabetical page labels. This may lead to denial of service or resource exhaustion but does not indicate code execution or data compromise.
Mitigation Recommendations
Upgrade to pypdf version 6.19.0 where the vulnerability is fixed. If immediate upgrade is not possible, apply the changes from pull request #4096 as a temporary workaround.
Technical Details
- Gcve Source
- db.gcve.eu
- Osv Id
- BREW-pdfly-CVE-2026-103000
- Osv Schema Version
- 1.7.3
- Ecosystems
- ["Homebrew"]
- Cvss Version
- 4.0
- State
- PUBLISHED
Threat ID: 6ac13971a43b0b3b89d5fe13
Added to database: 10/03/2026, 17:20:49 UTC
Last enriched: 10/03/2026, 17:27:09 UTC
Last updated: 10/04/2026, 02:46:02 UTC
Views: 3
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