[SECURITY] Update dependency fast-xml-parser to v5.3.8

[specmatic-builder]

This PR contains the following updates:

Package	Change	Age	Adoption	Passing	Confidence
fast-xml-parser	5.3.6 → 5.3.8

GitHub Vulnerability Alerts

CVE-2026-27942

Impact

Application crashes with stack overflow when user use XML builder with prserveOrder:true for following or similar input:

[{
    'foo': [
        { 'bar': [{ '@​_V': 'baz' }] }
    ]
}]

Cause: arrToStr was not validating if the input is an array or a string and treating all non-array values as text content.
What kind of vulnerability is it? Who is impacted?

Patches

Yes, in 5.3.8 and 4.5.4.

Workarounds

Use XML builder with preserveOrder:false or check the input data before passing to builder.

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fast-xml-parser has stack overflow in XMLBuilder with preserveOrder

CVE-2026-27942 / GHSA-fj3w-jwp8-x2g3

More information

Details

Impact

Application crashes with stack overflow when user use XML builder with prserveOrder:true for following or similar input:

[{
    'foo': [
        { 'bar': [{ '@​_V': 'baz' }] }
    ]
}]

Cause: arrToStr was not validating if the input is an array or a string and treating all non-array values as text content.
What kind of vulnerability is it? Who is impacted?

Patches

Yes, in 5.3.8 and 4.5.4.

Workarounds

Use XML builder with preserveOrder:false or check the input data before passing to builder.

Severity

• CVSS Score: 2.7 / 10 (Low)
• Vector String: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:U

References

• https://github.com/NaturalIntelligence/fast-xml-parser/security/advisories/GHSA-fj3w-jwp8-x2g3
• https://nvd.nist.gov/vuln/detail/CVE-2026-27942
• https://github.com/NaturalIntelligence/fast-xml-parser/pull/791
• https://github.com/NaturalIntelligence/fast-xml-parser/commit/c13a961910f14986295dd28484eee830fa1a0e8a
• https://github.com/NaturalIntelligence/fast-xml-parser

This data is provided by OSV and the GitHub Advisory Database (CC-BY 4.0).

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Release Notes

NaturalIntelligence/fast-xml-parser (fast-xml-parser)

v5.3.8: handle non-array input for XML builder && support maxNestedTags

Compare Source

• support maxNestedTags
• handle non-array input for XML builder when preserveOrder is true (By Angelo Coetzee)
• save use of js properies
  Full Changelog: NaturalIntelligence/fast-xml-parser@v5.3.7...v5.3.8

v5.3.7: CJS typing fix

Compare Source

What's Changed

• Unexport X2jOptions at declaration site by @​Drarig29 in #​787

New Contributors

• @​Drarig29 made their first contribution in #​787

Full Changelog: NaturalIntelligence/fast-xml-parser@v5.3.6...v5.3.7

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