CVE-2026-24515: CWE-476 NULL Pointer Dereference in libexpat project libexpat
In libexpat before 2.7.4, XML_ExternalEntityParserCreate does not copy unknown encoding handler user data.
AI Analysis
Technical Summary
In libexpat prior to version 2.7.4, the XML_ExternalEntityParserCreate function fails to copy user data associated with unknown encoding handlers. This results in a NULL pointer dereference (CWE-476) when the library attempts to access this missing data. The issue can cause application crashes, leading to denial of service conditions. The vulnerability is rated low severity with a CVSS 3.1 base score of 2.9, reflecting limited impact and exploitation difficulty. No vendor advisory or patch details are available at this time.
Potential Impact
The vulnerability can cause a denial of service by crashing applications that use the affected libexpat versions when processing XML with unknown encoding handlers. There is no impact on confidentiality or integrity. Exploitation requires local access and is complex, with no known exploits reported.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until an official fix is released, avoid processing untrusted XML data with unknown encoding handlers or consider upgrading to libexpat version 2.7.4 or later once available.
CVE-2026-24515: CWE-476 NULL Pointer Dereference in libexpat project libexpat
Description
In libexpat before 2.7.4, XML_ExternalEntityParserCreate does not copy unknown encoding handler user data.
CVSS v3.1
Score 2.9low
Affected software
libexpat project
libexpat
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Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
In libexpat prior to version 2.7.4, the XML_ExternalEntityParserCreate function fails to copy user data associated with unknown encoding handlers. This results in a NULL pointer dereference (CWE-476) when the library attempts to access this missing data. The issue can cause application crashes, leading to denial of service conditions. The vulnerability is rated low severity with a CVSS 3.1 base score of 2.9, reflecting limited impact and exploitation difficulty. No vendor advisory or patch details are available at this time.
Potential Impact
The vulnerability can cause a denial of service by crashing applications that use the affected libexpat versions when processing XML with unknown encoding handlers. There is no impact on confidentiality or integrity. Exploitation requires local access and is complex, with no known exploits reported.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until an official fix is released, avoid processing untrusted XML data with unknown encoding handlers or consider upgrading to libexpat version 2.7.4 or later once available.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mitre
- Date Reserved
- 2026-01-23T07:46:36.099Z
- Cvss Version
- 3.1
- State
- PUBLISHED
Threat ID: 697328604623b1157c1b2149
Added to database: 01/23/2026, 07:50:56 UTC
Last enriched: 06/02/2026, 20:07:45 UTC
Last updated: 09/10/2026, 22:19:51 UTC
Views: 352
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