CVE-2026-71403 — Rancher: Identity-field mutation in /v3/users allows account hijack via principal rebind

CVE-2026-71403

Rancher: Identity-field mutation in /v3/users allows account hijack via principal rebind PUBLISHED

Description (CNA)

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 (CNA)

Vendor / product	Versions
SUSE / Rancher	affected 0 before 2.15.1

CWE

CWE-639

References

https://github.com/rancher/rancher/pull/56616

ADP enrichment

CISA-ADP

No English description supplied.

No references supplied.