CVE-2026-25705 | Rancher Extensions have arbitrary file access via path traversal

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.

Published: 2026-05-13 Last update: 2026-05-13 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2026-25705 is rated Low Risk (38.1/100): CVSS High severity, with low exploitation likelihood (EPSS 0.04%). Mandatory action: Monitor for updates and reassess as exploit intelligence or EPSS changes.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2026-25705

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-05-13 0.04%

Full EPSS history (1 record total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-25705

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
8.4 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:H/I:H/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:H)
They need powerful rights—admin, root, or similar—before this pays off.
User interaction (UI:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:C)
Breaking this can reach past the original component and bite other resources—bigger blast radius.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
1.7 6.0 [email protected]

Weakness enumeration for CVE-2026-25705

GitHub Security Advisory for CVE-2026-25705

GHSA-5v3h-x4wf-5c35 · Severity: high · Ecosystem: go — Rancher Extensions have arbitrary file access via path traversal

Affected software / configurations for CVE-2026-25705

Vendor Product Version Raw CPE
No affected products in dataset.

References for CVE-2026-25705

cvelogic Threat Intelligence