GHSA-q82v-h4rq-5c86 — rancher
HIGHGHSA-q82v-h4rq-5c86 is a high-severity (CVSS 7.6) CWE-863 vulnerability in github.com/rancher/rancher. A fix is available for github.com/rancher/rancher — see the affected versions and patch details below.
Rancher update on users can deny the service to the admin
Exploitation Status
No confirmed exploitation observed yet
- 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 GHSA-q82v-h4rq-5c86.
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
GHSA-q82v-h4rq-5c86 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 377,636 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 within Rancher Manager where a missing server-side validation on the .username field in Rancher can allow users with update permissions on other User resources to cause denial of access for targeted accounts. Specifically:
- Username takeover: A user with permission to update another user’s resource can set its
.usernameto "admin", preventing both the legitimate admin and the affected user from logging in, as Rancher enforces uniqueness at login time. - Account lockout: A user with update permissions on the admin account can change the admin’s username, effectively blocking administrative access to the Rancher UI.
This issue enables a malicious or compromised account with elevated update privileges on User resources to disrupt platform administration and user authentication.
Note: The users with these permissions to modify accounts and resources are considered as privileged users. For more information, please consult Rancher Manger’s documentation about global permissions.
Please consult the associated MITRE ATT&CK - Technique - Account Access Removal for further information about this category of attack.
Patches
This vulnerability is addressed by adding a new check in the webhook which blocks modifying usernames after it has been set. If it's empty then the username can be set to a username not already in use, but after that it is immutable.
Patched versions of Rancher include releases v2.12.2, v2.11.6, v2.10.10 and v2.9.12.
Workarounds
If you can't upgrade to a fixed version, please make sure that you are only granting update permissions on users’ related resources to trusted users.
References
If you have 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 our support matrix and product support lifecycle.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐹Go | github.com/rancher/rancher | ≥ 2.12.0&&< 2.12.2 | 2.12.2go get github.com/rancher/rancher@v2.12.2 |
| 🐹Go | github.com/rancher/rancher | ≥ 2.11.0&&< 2.11.6 | 2.11.6go get github.com/rancher/rancher@v2.11.6 |
| 🐹Go | github.com/rancher/rancher | ≥ 2.10.0&&< 2.10.10 | 2.10.10go get github.com/rancher/rancher@v2.10.10 |
| 🐹Go | github.com/rancher/rancher | ≥ 2.9.0&&< 2.9.12 | 2.9.12go get github.com/rancher/rancher@v2.9.12 |
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 2.12.2 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-q82v-h4rq-5c86 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 GHSA-q82v-h4rq-5c86 can be triaged on real exposure rather than presence alone.
Tailored to GHSA-q82v-h4rq-5c86. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is GHSA-q82v-h4rq-5c86 in your dependencies?
O3 Security finds GHSA-q82v-h4rq-5c86 across Go dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.