Description
A vulnerability has been identified in [Rancher's Extensions](https://ranchermanager.docs.rancher.com/integrations-in-rancher/rancher-extensions) where malicious code can be injected in Rancher through a path traversal in the `compressedEndpoint` field inside a `UIPlugin` deployment. A malicious UI extension could abuse that to: * Overwrite Rancher binaries or configuration to inject code. * Write to /var/lib/rancher/ to tamper with cluster state. * If hostPath volumes are mounted, write to the host node filesystem. * Use this issue to chain with other attack vectors.
References2
Metrics
- CVSS 3.1
-
8.4
HIGH
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:H/I:H/A:H - EPSS — exploit probability
- 0% percentile: 31 · as of 14 November 2026
- CWE
- CWE-35
Could this be exploited in your environment?
A patch closes the known hole. A penetration test shows what an attacker can still reach — with proof.