CVE-2026-86143
Last modified
CVE-2026-86143 is a high-severity vulnerability rated 7.3/10 on the CVSS scale. 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.. EPSS estimates a 0.12% chance of exploitation in the next 30 days.
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.
Metrics
Weakness Enumeration
Affected Software
| Vendor | Product | Versions |
|---|---|---|
| Xmlsoft | Libxml2 | < 2.15.4 |
References
Timeline
- Published
- Last Modified
- Status
- Analyzed
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