CVE-2026-25705 — rancher
HIGHCVE-2026-25705 is a high-severity (CVSS 8.4) CWE-35 vulnerability in github.com/rancher/rancher. A fix is available for github.com/rancher/rancher — see the affected versions and patch details below.
Rancher Extensions have arbitrary file access via path traversal
Exploitation Status
No confirmed exploitation observed yet
- A successful exploit gives an attacker total control of the affected component, not partial access.
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for CVE-2026-25705.
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
How urgent is this, really
CVE-2026-25705 plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.
Where this sits among everything scored
Of 378,156 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
Real-World Exposure
github.com/rancher/rancher🐹github.com/rancher/rancher🐹github.com/rancher/rancher🐹github.com/rancher/rancherReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Go packages — download data is not available via public APIs for these ecosystems.
Description
Impact
A vulnerability has been identified in Rancher's 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
hostPathvolumes are mounted, write to the host node filesystem. - Use this issue to chain with other attack vectors.
By default only the administrator can deploy UI extensions, unless permissions are granted to other users. It's always recommended to only install extensions that come from sources trusted by the user.
Please consult the associated MITRE CAPEC-126 - Technique - Path Traversal for further information about this category of attack.
Patches
This vulnerability is addressed by ensuring that:
- The file defined by the UI Plugin CR's
compressedEndpointhas to be created inside the cache directory and cannot contain../. If that is not possible, the installation will fail and the file won't be created. - The icons referenced by Cluster Repos'
index.yamlfile always resolves to a file inside the repository directory.
Patched versions of Rancher include releases v2.14.1, v2.13.5, v2.12.9, v2.11.13.
Workarounds
There is no workaround. The user must be careful about which UI Plugins they install.
Resources
If there are any questions or comments about this advisory:
- Reach out to the SUSE Rancher Security team for security related inquiries.
- Open an issue in the Rancher repository.
- Verify with the support matrix and product support lifecycle.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐹Go | github.com/rancher/rancher | ≥ 2.14.0&&< 2.14.1 | 2.14.1go get github.com/rancher/rancher@v2.14.1 |
| 🐹Go | github.com/rancher/rancher | ≥ 2.13.0&&< 2.13.5 | 2.13.5go get github.com/rancher/rancher@v2.13.5 |
| 🐹Go | github.com/rancher/rancher | ≥ 2.12.0&&< 2.12.9 | 2.12.9go get github.com/rancher/rancher@v2.12.9 |
| 🐹Go | github.com/rancher/rancher | ≥ 2.10.11&&< 2.11.13 | 2.11.13go get github.com/rancher/rancher@v2.11.13 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/rancher/rancher, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update github.com/rancher/rancher to 2.14.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-25705 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2026-25705 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2026-25705. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2026-25705 in your dependencies?
O3 Security finds CVE-2026-25705 across Go dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.