CVE-2026-27942 (GCVE-0-2026-27942)
Vulnerability from cvelistv5 – Published: 2026-02-26 01:22 – Updated: 2026-06-23 15:50
VLAI
EPSS
VEX
Title
fast-xml-parser has stack overflow in XMLBuilder with preserveOrder
Summary
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 with `preserveOrder:true`. Version 5.3.8 fixes the issue. As a workaround, use XML builder with `preserveOrder:false` or check the input data before passing to builder.
Severity
SSVC
Exploitation: none
Automatable: no
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-02-26 15:48 UTC
CWE
- CWE-120 - Buffer Copy without Checking Size of Input ('Classic Buffer Overflow')
Assigner
References
3 references
| URL | Tags |
|---|---|
| https://github.com/NaturalIntelligence/fast-xml-p… | x_refsource_CONFIRM |
| https://github.com/NaturalIntelligence/fast-xml-p… | x_refsource_MISC |
| https://github.com/NaturalIntelligence/fast-xml-p… | x_refsource_MISC |
Impacted products
1 product
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| NaturalIntelligence | fast-xml-parser |
Affected:
< 5.3.8
|
guessed |
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