How severe is CVE-2026-29186?

CVE-2026-29186 has a CVSS 3.x base score of 7.7, rated high severity. It is exploitable over network with high attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity low, and availability low.

Is CVE-2026-29186 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (52nd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-29186?

CVE-2026-29186 affects Linuxfoundation Backstage Plugin-techdocs-node. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-29186?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

Does CVE-2026-29186 have an EU (EUVD) identifier?

Yes. CVE-2026-29186 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-10146.

When was CVE-2026-29186 published?

CVE-2026-29186 was published on 2026-03-07 and last updated on 2026-06-30.

CVE-2026-29186

CVE-2026-29186 is a high-severity vulnerability in Linuxfoundation Backstage Plugin-techdocs-node with a CVSS 3.x base score of 7.7. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-74.

Key facts

Severity: High (CVSS 3.x base score 7.7)
EPSS exploit prediction: 1% (52nd percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-10146
Weakness: CWE-74
Affected product: Linuxfoundation Backstage Plugin-techdocs-node
Published: 2026-03-07
Last modified: 2026-06-30

Description

Backstage is an open framework for building developer portals. Prior to version 1.14.3, this is a configuration bypass vulnerability that enables arbitrary code execution. The @backstage/plugin-techdocs-node package uses an allowlist to filter dangerous MkDocs configuration keys during the documentation build process. A gap in this allowlist allows attackers to craft an mkdocs.yml that causes arbitrary Python code execution, completely bypassing TechDocs' security controls. This issue has been patched in version 1.14.3.

Frequently asked questions

What is CVE-2026-29186?: Backstage is an open framework for building developer portals. Prior to version 1.14.3, this is a configuration bypass vulnerability that enables arbitrary code execution. The @backstage/plugin-techdocs-node package uses an allowlist to filter dangerous MkDocs configuration keys during the documentation build process. A gap in this allowlist allows attackers to craft an mkdocs.yml that causes arbitrary Python code execution, completely bypassing TechDocs' security controls. This issue has been patched in version 1.14.3.
How severe is CVE-2026-29186?: CVE-2026-29186 has a CVSS 3.x base score of 7.7, rated high severity. It is exploitable over network with high attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity low, and availability low.
Is CVE-2026-29186 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (52nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-29186?: CVE-2026-29186 affects Linuxfoundation Backstage Plugin-techdocs-node. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-29186?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
Does CVE-2026-29186 have an EU (EUVD) identifier?: Yes. CVE-2026-29186 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-10146.
When was CVE-2026-29186 published?: CVE-2026-29186 was published on 2026-03-07 and last updated on 2026-06-30.

References

Affected products (1)

cpe:2.3:a:linuxfoundation:backstage_plugin-techdocs-node:*:*:*:*:*:*:*:*

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