Buffer overflow in Naturalintelligence Fast-xml-parser

CVE-2026-27942

fast-xml-parser allows users to validate XML, parse XML to JS object, or build XML from JS object without C/C++ based libraries and no callback. Prior to version 5.3.8, the application crashes with stack overflow when user use XML builder…

Vulnerability class: Buffer Overflow

EPSS: 0.000 (5.0th percentile) — read the EPSS interpretation.

Affected products

Naturalintelligence Fast-xml-parser — versions < 5.3.8

Weakness classification (CWE)

CWE-120 — Buffer Copy without Checking Size of Input (Classic Buffer Overflow)

References

https://github.com/NaturalIntelligence/fast-xml-parser/security/advisories/GHSA-fj3w-jwp8-x2g3 (x_refsource_CONFIRM)
https://github.com/NaturalIntelligence/fast-xml-parser/pull/791 (x_refsource_MISC)
https://github.com/NaturalIntelligence/fast-xml-parser/commit/c13a961910f14986295dd28484eee830fa1a0e8a (x_refsource_MISC)