CVE-2026-86143
CVSS Score
6.9
EPSS Score
0.0%
EPSS Percentile
0th
In xmlIO in libxml2 before 2.15.4, an inconsistency in xmlOutputWriteCallback and xmlBufUse causes negative lengths to reach write callbacks, aka a lack of a check for integer overflow before calling writecallback. This has security relevance for many types of uses of that length value within a callback.
| CWE | CWE-192 |
| Vendor | xmlsoft |
| Product | libxml2 |
| Published | Sep 5, 2026 |
| Last Updated | Sep 8, 2026 |
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CVSS v3 Breakdown
CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:L Attack Vector
Local
Attack Complexity
High
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
Low
Affected Versions
xmlsoft / libxml2
0 < 2.15.4