CVE-2026-86143
highIn 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 c…
Vendor / product: Xmlsoft — libxml2
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.
CVSS
7.3
7.3 (CVSS v3.1)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:L Severity source: NVD CVSS v3.1 (nvd@nist.gov)
Timeline (UTC)
Published: 2026-09-05 05:17
Modified: 2026-09-15 19:31
NVD status: Analyzed
Last synced 2 days ago
Verified against the source API 2026-10-27 06:50 UTC
Exploitation
Not listed in CISA KEV (as of last catalog sync)
Absence from KEV does not mean a CVE is not exploited. Exploitation status: unknown (no authoritative evidence in our sources).
Affected products
xmlsoft / libxml2 <2.15.4
Weakness classification (CWE)
Source: NVD / CISA. “NVD-CWE-Other” and “NVD-CWE-noinfo” mean NVD could not assign a specific weakness.
Mitigation & advisories
Vendor advisory: https://gitlab.gnome.org/GNOME/libxml2/-/work_items/1111
Patch / mitigation: https://github.com/GNOME/libxml2/commit/90f293ba74d28b1d570920382e707586f68ebf35
References
Data sources
NVD CVE API 2.0 — fetched 2026-10-27 06:50 UTC · record ↗