4.9

CVE-2026-106499: backstage

CVSS: 4.9v3.1MediumAnalyzed
AliasesGHSA-mfvq-x7vr-rgqg
Published 06-10-2026Last modified 07-10-2026
Open JSON

Vulnerability summary

CVE-2026-106499 is a medium (CVSS 4.9) vulnerability in backstage. EPSS estimates a 0.27% chance of exploitation in the next 30 days, higher than 17.9% of scored vulnerabilities.

Overall risk
20/100
0100
Low · default modelHow is this calculated?
CVSS score
4.9/10
010
Medium · v3.1 (CVE.org)
EPSS score
0.27%
0%100%
Low · Change unavailable
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Timeline

  1. 06-10-2026
    PublishedVulnerability first disclosed.
  2. 07-10-2026
    Last modifiedVulnerability information updated.

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 metrics

3 scores · 3 sources · 1 version

EPSS trend

Probability

0.27%

Chance of exploitation in the next 30 days

Percentile

18%

Versus all other CVEs

30-day change

Change unavailable

Change unavailable

07-10-202619-10-2026
EPSS score
0.27%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

@backstage2 products
Linuxfoundation2 products
Backstage1 product

3 vendors · 5 products

References

5 links