Intel

CVE-2026-106499

@backstage/plugin-scaffolder-backend: Insertion of Sensitive Information into Log File (CVE-2026-106499)

mediumEPSS 0.3%

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.

Source: cvelistv5NVD (NIST)OSV (Open Source Vulnerabilities)GitHub Security Advisories

Affected products

The following versions are affected. Older releases of the same product line are also vulnerable unless stated otherwise.

npm@backstage/plugin-scaffolder-backend

Metrics

XIEM Effective CVSS
4.9
Source: cna-v3
EPSS percentile
17.5 %
Elevated — this CVE ranks above at least 10% of all CVEs scored today.
KEV status
—
Show all metrics
Severity
medium
Priority score
56.96
Exploit maturity
no public PoC known
CVSS v3
4.9
EPSS score
0.3 %
Low — model estimates < 1% exploitation likelihood.
Published
2026-10-07 17:59 UTC
CWE
CWE-532

Weakness classes (CWE)

  • CWE-532Base

    Insertion of Sensitive Information into Log File

    The product writes sensitive information to a log file.

    cwe.mitre.org →

References & sources

Reanalysis & status changes

Chronological NVD audit events for this CVE — reanalyses, CVSS updates, CPE diffs.

  1. CVE Modified2026-10-07 18:17 UTC· 134c704f-9b21-4f2e-91b3-4a467353bcc0
    • SSVC: {"id":"CVE-2026-106499","role":"CISA Coordinator","options":[{"exploitation":"none"},{"automatable":"no"},{"technical…
  2. New CVE Received2026-10-06 22:17 UTC· security-advisories@github.com
    • 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.
    • CVSS V3.1: AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:N/A:N
    • CWE: CWE-532
    • Affected: New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/106xxx/CVE-2026-106499.json">CVE-2026-106499</a>