Rancher Recreates Default User With Known Password Despite DeletionGHSA-xh8x-j8h3-m5ph
CRITICALGHSA-xh8x-j8h3-m5ph is a critical-severity (CVSS 9.8) Improper Authentication vulnerability in github.com/rancher/rancher. A fix is available for github.com/rancher/rancher — see the affected versions and patch details below.
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
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Real-World Exposure
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
An issue was discovered that affects the following versions of Rancher: v2.0.0 through v2.0.13, v2.1.0 through v2.1.8, and v2.2.0 through 2.2.1. When Rancher starts for the first time, it creates a default admin user with a well-known password. After initial setup, the Rancher administrator may choose to delete this default admin user. If Rancher is restarted, the default admin user will be recreated with the well-known default password. An attacker could exploit this by logging in with the default admin credentials. This can be mitigated by deactivating the default admin user rather than completing deleting them.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐹Go | github.com/rancher/rancher | ≥ 2.0.0 | No fix |
| 🐹Go | github.com/rancher/rancher | ≥ 2.1.0 | No fix |
| 🐹Go | github.com/rancher/rancher | ≥ 2.2.0&&< 2.2.2 | 2.2.2go get github.com/rancher/rancher@v2.2.2 |
Affected Products
ranchersuseDetection & 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
A fix is available for GHSA-xh8x-j8h3-m5ph; check the affected-versions list above or the advisory for the patched release of github.com/rancher/rancher, then make sure no transitive dependency still pins the vulnerable range.
Workarounds
Put an independent control in front of the weakness: restrict the affected endpoint or interface to trusted networks, require an additional authentication factor or proxy-level check, and invalidate existing sessions and credentials in case the flaw has already been used.
Frequently Asked Questions
Is GHSA-xh8x-j8h3-m5ph in your dependencies?
Find it across Go, including transitive dependencies.