How severe is CVE-2026-106504?

CVE-2026-106504 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.

Is CVE-2026-106504 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (16th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-106504?

CVE-2026-106504 primarily affects Linuxfoundation Backstage/plugin-scaffolder-backend. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2026-106504?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2026-106504 published?

CVE-2026-106504 was published on 2026-10-06 and last updated on 2026-10-13.

CVE-2026-106504

CVE-2026-106504 is a medium-severity vulnerability in Linuxfoundation Backstage/plugin-scaffolder-backend with a CVSS 3.x base score of 6.5. 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-532.

Key facts

Severity: Medium (CVSS 3.x base score 6.5)
EPSS exploit prediction: 0% (16th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-532
Affected product: Linuxfoundation Backstage/plugin-scaffolder-backend
Published: 2026-10-06
Last modified: 2026-10-13

Description

Backstage is an open framework for building developer portals. Prior to 4.1.0, the @backstage/plugin-scaffolder-backend package is affected by sensitive information exposure in scaffolder task logs. An authenticated user who can create and read scaffolder tasks may be able to observe sensitive values in task logs in deployments with restrictive action permissions and affected templates. Exploitation requires a denied action whose input contains such a value. This issue is fixed in version 4.1.0.

Frequently asked questions

What is CVE-2026-106504?: Backstage is an open framework for building developer portals. Prior to 4.1.0, the @backstage/plugin-scaffolder-backend package is affected by sensitive information exposure in scaffolder task logs. An authenticated user who can create and read scaffolder tasks may be able to observe sensitive values in task logs in deployments with restrictive action permissions and affected templates. Exploitation requires a denied action whose input contains such a value. This issue is fixed in version 4.1.0.
How severe is CVE-2026-106504?: CVE-2026-106504 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.
Is CVE-2026-106504 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (16th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-106504?: CVE-2026-106504 primarily affects Linuxfoundation Backstage/plugin-scaffolder-backend. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2026-106504?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2026-106504 published?: CVE-2026-106504 was published on 2026-10-06 and last updated on 2026-10-13.

References

Affected products (2)

cpe:2.3:a:linuxfoundation:backstage\/plugin-scaffolder-backend:*:*:*:*:*:*:*:*
cpe:2.3:a:linuxfoundation:backstage:*:*:*:*:*:*:*:*

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CVE-2026-106502 — Medium (CVSS 5.3): Backstage is an open framework for building developer portals. Prior to 4.1.0, the @backstage/plugin-scaffolder-backend…

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