4.3

CVE-2026-106495: @backstage backend-defaults Improper Access Control

CVSS: 4.3v3.1MediumAwaiting analysis
AliasesGHSA-3xr5-8w6c-p5gw
Published 12-10-2026Last modified 13-10-2026
Open JSON

Vulnerability summary

CVE-2026-106495 is a medium (CVSS 4.3) Improper Access Control vulnerability in @backstage backend-defaults. EPSS estimates a 0.24% chance of exploitation in the next 30 days, higher than 13.9% of scored vulnerabilities.

Overall risk
17/100
0100
Low · default modelHow is this calculated?
CVSS score
4.3/10
010
Medium · v3.1 (NVD)
EPSS score
0.24%
0%100%
Low · Change unavailable
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Timeline

  1. 12-10-2026
    PublishedVulnerability first disclosed.
  2. 13-10-2026
    Last modifiedVulnerability information updated.

Description

Backstage is an open framework for building developer portals. Prior to 0.17.8, the @backstage/backend-defaults package is affected by improper access control in backend action invocation. An authenticated user could invoke actions that an operator had excluded through action configuration. Existing action permissions and downstream authorization remain enforced. This issue is fixed in version 0.17.8.

CVSS metrics

3 scores · 3 sources · 1 version

EPSS trend

Probability

0.24%

Chance of exploitation in the next 30 days

Percentile

14%

Versus all other CVEs

30-day change

Change unavailable

Change unavailable

13-10-202620-10-2026
EPSS score
0.24%

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