CVE-2026-86143

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 v3 6.9 MEDIUM

6.9^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.4 / Impact : 5.5

Attack Vector LOCAL

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
https://github.com/GNOME/libxml2/commit/90f293ba74d28b1d570920382e707586f68ebf35	Patch
https://github.com/GNOME/libxml2/compare/v2.15.3...v2.15.4	Release Notes
https://gitlab.gnome.org/GNOME/libxml2/-/work_items/1111	Exploit Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:xmlsoft:libxml2:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-09-05 05:17

Updated : 2026-09-15 19:31

NVD link : CVE-2026-86143

Mitre link : CVE-2026-86143

CVE.ORG link : CVE-2026-86143

JSON object : View

Products Affected

xmlsoft

libxml2

CWE

CWE-192

Integer Coercion Error

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