CVE-2026-86142: CWE-122 Heap-based Buffer Overflow in xmlsoft libxml2
Description
In libxml2 before 2.15.4, there is a heap-based buffer overflow in xmlXPtrEvalXPtrPart because of xmlXPtrEval xpointer length saturation.
CVSS v3.1
Score 6.9medium
Affected software
xmlsoft
libxml2
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-86142 is a heap-based buffer overflow vulnerability in the xmlXPtrEvalXPtrPart function of libxml2 prior to version 2.15.4. The issue arises from xmlXPtrEval's handling of xpointer length saturation, which can cause memory corruption. The vulnerability has a CVSS 3.1 base score of 6.9, indicating medium severity with high impact on confidentiality and integrity, and low impact on availability. The vulnerability requires local access with high attack complexity and no privileges or user interaction.
Potential Impact
Exploitation of this vulnerability can lead to unauthorized disclosure or modification of data due to heap memory corruption. The availability impact is low. The attack requires local access and is complex to execute.
Mitigation Recommendations
A fix is available in libxml2 version 2.15.4. Users should upgrade to version 2.15.4 or later to remediate this vulnerability. No vendor advisory content was provided to indicate alternative mitigations or that no action is required.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mitre
- Date Reserved
- 2026-09-05T04:29:32.967Z
- Cvss Version
- 3.1
- State
- PUBLISHED
Threat ID: 6a9b9ca2acd9273b49507019
Added to database: 09/05/2026, 04:37:54 UTC
Last enriched: 09/14/2026, 23:28:10 UTC
Last updated: 10/20/2026, 06:48:19 UTC
Views: 103
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