CVE-2022-43755 — rancher
HIGHCVE-2022-43755 is a high-severity (CVSS 7.1) CWE-331 vulnerability in github.com/rancher/rancher. A fix is available for github.com/rancher/rancher — see the affected versions and patch details below.
Rancher: Non-random authentication token
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-2022-43755.
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
Where this sits among everything scored
Real-World Exposure
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
An issue was discovered in Rancher versions up to and including 2.6.9 and 2.7.0, where the cattle-token secret, used by the cattle-cluster-agent, is predictable. Even after the token is regenerated, it will have the same value. This issue is not present in Rancher 2.5 releases.
The cattle-token is used by Rancher's cattle-cluster-agent to connect to the Kubernetes API of Rancher provisioned downstream clusters. The problem occurs because the cattle-token secret does not use any random value in its composition, which causes it to always be regenerated with the same value. This can pose a serious problem if the token is compromised and needs to be recreated for security purposes.
The usage of the cattle-token by an unauthorized user allows to escalate privileges to the cluster owner of the affected downstream cluster. It does not allow access to Rancher's own local cluster (the cluster where Rancher is provisioned).
Workarounds
In case it is not possible to promptly update to a patched version, a workaround is to use the rotate script provided in the public security advisory CVE-2021-36782 / GHSA-g7j7-h4q8-8w2f, which facilitates the rotation and creation of a new unique downstream cluster token.
Patches
Patched versions include releases 2.6.10, 2.7.1 and later versions.
After upgrading to one of the patched versions, it is highly recommended to rotate the cattle-token in downstream clusters to guarantee that a new random token will be safely regenerated.
The procedure below can rotate the cattle-token and should be executed in each downstream cluster provisioned by Rancher. It is recommended to first test this process in an appropriate development/testing environment.
# Verify the current secret before rotating it
$ kubectl describe secrets cattle-token -n cattle-system
# Delete the secret
$ kubectl delete secrets cattle-token -n cattle-system
# Restart the cattle-cluster-agent deployment
$ kubectl rollout restart deployment/cattle-cluster-agent -n cattle-system
# Confirm that a new and different secret was generated
$ kubectl describe secrets cattle-token -n cattle-system
For more information
If you have any questions or comments about this advisory:
- Reach out to SUSE Rancher Security team for security related inquiries.
- Open an issue in Rancher repository.
- Verify our support matrix and product support lifecycle.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐹Go | github.com/rancher/rancher | ≥ 2.6.0&&< 2.6.10 | 2.6.10go get github.com/rancher/rancher@v2.6.10 |
| 🐹Go | github.com/rancher/rancher | ≥ 2.7.0&&< 2.7.1 | 2.7.1go get github.com/rancher/rancher@v2.7.1 |
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
Update github.com/rancher/rancher to 2.6.10 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2022-43755 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.
Frequently Asked Questions
Is CVE-2022-43755 in your dependencies?
Find it across Go, including transitive dependencies.