CVE-2026-42457 PUBLISHED

vCluster Platform: Stored XSS can lead to privilege escalation

Assigner: GitHub_M
Reserved: 27.04.2026 Published: 14.05.2026 Updated: 14.05.2026

vCluster Platform provides a Kubernetes platform for managing virtual clusters, multi-tenancy, and cluster sharing. Prior to 4.4.3, 4.5.5, 4.6.2, 4.7.1, and 4.8.0, there is a Stored XSS attack vulnerability via the name field of a templateRef. This can lead to the execution of arbitrary external scripts within the platform's browser context. In the worst case, a malicious user could potentially create a new Global-Admin user, bypassing other security restrictions. The attacker needs the ability to create namespaces. This vulnerability is fixed in 4.4.3, 4.5.5, 4.6.2, 4.7.1, and 4.8.0.

Metrics

CVSS Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:H
CVSS Score: 9

Product Status

Vendor loft-sh
Product loft
Versions
  • Version < 4.4.3 is affected
  • Version >=4.5.0-alpha.0 , < 4.5.5 is affected
  • Version >= 4.6.0-alpha.1, < 4.6.2 is affected
  • Version >= 4.7.0-alpha.0, < 4.7.1 is affected

References

Problem Types

  • CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') CWE