CVE-2026-40260: CWE-776: Improper Restriction of Recursive Entity References in DTDs ('XML Entity Expansion') in py-pdf pypdf
CVE-2026-40260 is a medium severity vulnerability in the py-pdf pypdf library versions prior to 6. 10. 0. It involves improper restriction of recursive entity references in XML DTDs, specifically in XMP metadata parsing. An attacker can craft a PDF with manipulated XMP metadata entity declarations that cause excessive memory consumption, potentially exhausting system RAM. This vulnerability has been fixed in pypdf version 6. 10. 0.
AI Analysis
Technical Summary
The vulnerability CVE-2026-40260 in py-pdf's pypdf library (versions before 6.10.0) is due to improper restriction of recursive XML entity references (CWE-776) in XMP metadata. When parsing such crafted XMP metadata, the library can be forced to consume large amounts of memory, leading to exhaustion of RAM. This issue is addressed by the fix introduced in version 6.10.0 of pypdf.
Potential Impact
Exploitation of this vulnerability allows an attacker to cause high memory usage on systems parsing malicious PDFs with crafted XMP metadata. This can lead to denial of service conditions due to resource exhaustion. There is no indication of code execution or data corruption from the provided data.
Mitigation Recommendations
This vulnerability is fixed in pypdf version 6.10.0. Users should upgrade to version 6.10.0 or later to remediate this issue. Since no official patch link or advisory is provided, users should verify upgrade availability from the official py-pdf project sources. No additional mitigation steps are indicated.
CVE-2026-40260: CWE-776: Improper Restriction of Recursive Entity References in DTDs ('XML Entity Expansion') in py-pdf pypdf
Description
CVE-2026-40260 is a medium severity vulnerability in the py-pdf pypdf library versions prior to 6. 10. 0. It involves improper restriction of recursive entity references in XML DTDs, specifically in XMP metadata parsing. An attacker can craft a PDF with manipulated XMP metadata entity declarations that cause excessive memory consumption, potentially exhausting system RAM. This vulnerability has been fixed in pypdf version 6. 10. 0.
CVSS v4.0
Score 6.9medium
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The vulnerability CVE-2026-40260 in py-pdf's pypdf library (versions before 6.10.0) is due to improper restriction of recursive XML entity references (CWE-776) in XMP metadata. When parsing such crafted XMP metadata, the library can be forced to consume large amounts of memory, leading to exhaustion of RAM. This issue is addressed by the fix introduced in version 6.10.0 of pypdf.
Potential Impact
Exploitation of this vulnerability allows an attacker to cause high memory usage on systems parsing malicious PDFs with crafted XMP metadata. This can lead to denial of service conditions due to resource exhaustion. There is no indication of code execution or data corruption from the provided data.
Mitigation Recommendations
This vulnerability is fixed in pypdf version 6.10.0. Users should upgrade to version 6.10.0 or later to remediate this issue. Since no official patch link or advisory is provided, users should verify upgrade availability from the official py-pdf project sources. No additional mitigation steps are indicated.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- GitHub_M
- Date Reserved
- 2026-04-10T17:31:45.787Z
- Cvss Version
- 4.0
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 69e1716682d89c981fde6ff3
Added to database: 4/16/2026, 11:31:50 PM
Last enriched: 4/24/2026, 4:15:26 PM
Last updated: 5/31/2026, 1:53:42 PM
Views: 97
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