What’s Vulnerable › Vulnerabilities
CVE-2026-71403: Rancher: Identity-field mutation in /v3/users allows account hijack via principal rebind
- Severity: medium (CVSS 6.1 v3.1)
- Exploited in the wild: not listed in CISA KEV
- EPSS: 0.4% probability of exploitation in the next 30 days
- Public exploit or detection template: none known
- Published: 2026-09-03 · updated 2026-09-18
- Weakness: CWE-639
Description
A flaw was found in Rancher Manager. The /v3/users update path did not enforce immutability of a User resource's `username` and `principalIds` fields. A user holding the `update` verb on `users.management.cattle.io` could inject a foreign identity provider principal into any account, so that the next login by the owner of that principal was bound to the victim's account and inherited its role bindings. This issue affects Rancher: before 2.15.1.
Affected products
- SUSE Rancher: before 2.15.1 — fixed in 2.15.1
How to fix
Upgrade to a fixed version: SUSE Rancher 2.15.1. Check the vendor advisory for mitigations.
References
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