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.
Affected products
xmlsoft: libxml2
References3
- gitlab.gnome.org/GNOME/libxml2/-/work_items/1111 ExploitVendor Advisory
- github.com/GNOME/libxml2/commit/90f293ba74d28b1d570920382e70758… Patch
- github.com/GNOME/libxml2/compare/v2.15.3...v2.15.4 Release Notes
Metrics
- CVSS 3.1
-
7.3
HIGH
Score source: NVD
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:L - EPSS — exploit probability
- 0% percentile: 9 · as of 7 November 2026
- CWE
- CWE-192
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