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HIGH

CVE-2026-27942

CVSS v3

7.5

HIGH

EPSS Score

0.7 %

exploit probability, as of 2026-10-17

CISA KEV

No

known exploited

Exploitation

—

SSVC status

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Affected and fixed versions

Packages from OSV.dev and products from the vendors' CSAF advisories.

version not verifiedVersions not verified: read as OSV.dev and the vendors publish them, not checked against each vendor's release list.

Packages

  • fast-xml-parsernpmfrom 4.0.0-beta.0 · fixed in 4.5.4

Vendor advisories

  • CVE-2026-27942 Red Hat Product Security333 products fixed · 4 known affected

    fast-xml-parser: fast-xml-parser: Stack overflow leads to Denial of Service

    mta/mta-ui-rhel9 as a component of Migration Toolkit for Applications 8 · openshift-gitops-1/argocd-rhel8 as a component of Red Hat OpenShift GitOps · openshift-gitops-1/argocd-rhel9 as a component of Red Hat OpenShift GitOps

  • RHSA-2026:51349 Red Hat Product Security1 product fixed

    Red Hat Security Advisory: General availability of the satellite/iop-host-inventory-frontend-rhel9 container image

  • RHSA-2026:41944 Red Hat Product Security78 products fixed

    Red Hat Security Advisory: Red Hat OpenShift Data Foundation 4.19.20 security, enhancement & bug fix update

  • RHSA-2026:41941 Red Hat Product Security68 products fixed

    Red Hat Security Advisory: Red Hat OpenShift Data Foundation 4.18.25 security, enhancement & bug fix update

  • RHSA-2026:40984 Red Hat Product Security88 products fixed

    Red Hat Security Advisory: Red Hat OpenShift Data Foundation 4.20.15 security, enhancement & bug fix update

  • RHSA-2026:12277 Red Hat Product Security88 products fixed

    Red Hat Security Advisory: Red Hat OpenShift Data Foundation 4.20.10 security, enhancement & bug fix update

4 more advisories

Full record on NVD

Description

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.

Technical details

CVSS v3 Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Published
2026-02-26
Last Modified
2026-03-02

Frequently asked questions

What is 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 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.

Is CVE-2026-27942 actively exploited?

Active exploitation of CVE-2026-27942 has not been confirmed. Its EPSS score was 0.7% on 2026-10-17, the estimated probability of exploitation in the next 30 days.

What is the CVSS score for CVE-2026-27942?

CVE-2026-27942 has a CVSS v3 base score of 7.5 (HIGH severity), with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.

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