CVE-2026-86143
MEDIUM
NVD
CVSS Score
6.9
Severity
MEDIUM
Published
Sep 05, 2026
Vendor
unknown
Description
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.