8.1

CVE-2026-106488: backstage Improper Authentication

CVSS: 8.1v3.1HighUndergoing analysis
AliasesGHSA-826h-28h9-65hg
Published 06-10-2026Last modified 07-10-2026
Open JSON

Vulnerability summary

CVE-2026-106488 is a high (CVSS 8.1) Improper Authentication vulnerability in backstage. EPSS estimates a 0.28% chance of exploitation in the next 30 days, higher than 19.2% of scored vulnerabilities.

Overall risk
32/100
0100
Medium · default modelHow is this calculated?
CVSS score
8.1/10
010
High · v3.1 (CVE.org)
EPSS score
0.28%
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 0.4.20, the @backstage/plugin-auth-backend-module-oidc-provider package is affected by improper authentication in the oidc provider. Deployments using OIDC email-based identity resolution with a provider that permits unverified email addresses may allow an authenticated provider user to assume another catalog identity. This may grant access and permissions associated with that user. No direct availability impact is demonstrated. This issue is fixed in version 0.4.20.

CVSS metrics

3 scores · 3 sources · 1 version

EPSS trend

Probability

0.28%

Chance of exploitation in the next 30 days

Percentile

19%

Versus all other CVEs

30-day change

Change unavailable

Change unavailable

07-10-202620-10-2026
EPSS score
0.28%

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
Backstage1 product

2 vendors · 3 products

References

5 links