CVE-2026-106499

Backstage: Secret-derived values may be exposed in scaffolder task logs

MEDIUM 4.9

At a glance

Source: NVD
EPSS: EPSS 0.27 % · percentile 19 (2026-10-28)
State: PUBLISHED
Published: 2026-10-06 21:25 UTC
Updated: 2026-10-07 17:46 UTC
Assigner: GitHub_M
NVD status: Analyzed

Description

Backstage is an open framework for building developer portals. Prior to 4.1.0, the @backstage/plugin-scaffolder-backend package could expose secret-derived values in Scaffolder task logs. Deployments that configure sensitive scaffolder.defaultEnvironment.secrets and allow an attacker to create or modify Scaffolder templates are affected. A template author could cause secret-derived values used during template iteration to be persisted and exposed to users who can access the resulting task logs. This issue is fixed in version 4.1.0.

Weaknesses (CWE)

CWE-532 — Insertion of Sensitive Information into Log File

References

Scores

Version	Score	Vector	Scored by
CVSS 3.1	MEDIUM 4.9	CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:N/A:N	GitHub_M
CVSS 3.1	MEDIUM 4.9	CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:N/A:N	NVD · security-advisories@github.com (Secondary)

Advisories

GHSA-mfvq-x7vr-rgqg — Backstage: Secret-derived values may be exposed in scaffolder task logs

European references

ENISA EUVD · EUVD-2026-94057
GCVE · GCVE-0-2026-106499

Affected configurations (NVD CPE)

cpe:2.3:a:linuxfoundation:backstage\/plugin-scaffolder-backend:*:*:*:*:*:*:*:* < 4.1.0
cpe:2.3:a:linuxfoundation:backstage:*:*:*:*:*:*:*:* < 1.54.6

Affected products

Product	Versions
backstage · backstage	affected < 1.54.6
@backstage · plugin-scaffolder-backend	affected < 4.1.0

Sources

Source	Licence
CVE List (CVEProject cvelistV5)	CVE Program Terms of Use
EPSS (FIRST.org)	FIRST — attribution requested
ENISA EUVD	ENISA — reproduction authorised, source acknowledged
NVD (NIST) via fkie-cad/nvd-json-data-feeds	Public domain — this product uses data from the NVD API but is not endorsed or certified by the NVD