x/vulndb: potential Go vuln in github.com/rancher/rancher: GHSA-8c69-r38j-rpfj #1514
Description
In GitHub Security Advisory GHSA-8c69-r38j-rpfj, there is a vulnerability in the following Go packages or modules:
| Unit | Fixed | Vulnerable Ranges |
|---|---|---|
| github.com/rancher/rancher | 2.7.1 | >= 2.7.0, < 2.7.1 |
Cross references:
- Module github.com/rancher/rancher appears in issue x/vulndb: potential Go vuln in github.com/rancher/rancher: GHSA-wm2r-rp98-8pmh #439 EFFECTIVELY_PRIVATE
- Module github.com/rancher/rancher appears in issue x/vulndb: potential Go vuln in github.com/rancher/rancher: CVE-2022-21951 #464 EFFECTIVELY_PRIVATE
- Module github.com/rancher/rancher appears in issue x/vulndb: potential Go vuln in github.com/rancher/rancher: GHSA-4fc7-hc63-7fjg #551 EFFECTIVELY_PRIVATE
- Module github.com/rancher/rancher appears in issue x/vulndb: potential Go vuln in github.com/rancher/rancher: GHSA-hx8w-ghh8-r4xf #605 EFFECTIVELY_PRIVATE
- Module github.com/rancher/rancher appears in issue x/vulndb: potential Go vuln in github.com/rancher/rancher: GHSA-jwvr-vv7p-gpwq, CVE-2021-36784 #610 EFFECTIVELY_PRIVATE
- Module github.com/rancher/rancher appears in issue x/vulndb: potential Go vuln in github.com/rancher/rancher: GHSA-9qq2-xhmc-h9qr #644 EFFECTIVELY_PRIVATE
- Module github.com/rancher/rancher appears in issue x/vulndb: potential Go vuln in github.com/rancher/rancher: CVE-2021-36782 #973 EFFECTIVELY_PRIVATE
- Module github.com/rancher/rancher appears in issue x/vulndb: potential Go vuln in github.com/rancher/rancher: CVE-2021-36783 #974 EFFECTIVELY_PRIVATE
- Module github.com/rancher/rancher appears in issue x/vulndb: potential Go vuln in github.com/rancher/rancher: CVE-2022-31247 #975 EFFECTIVELY_PRIVATE
- Module github.com/rancher/rancher appears in issue x/vulndb: potential Go vuln in github.com/rancher/rancher/server: GHSA-xhg2-rvm8-w2jh #755
See doc/triage.md for instructions on how to triage this report.
modules:
- module: github.com/rancher/rancher
versions:
- introduced: 2.7.0
fixed: 2.7.1
packages:
- package: github.com/rancher/rancher
- module: github.com/rancher/rancher
versions:
- introduced: 2.6.0
fixed: 2.6.10
packages:
- package: github.com/rancher/rancher
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](https://github.com/rancherlabs/support-tools/tree/master/rotate-tokens) provided in the public security advisory [CVE-2021-36782 / GHSA-g7j7-h4q8-8w2f](https://github.com/rancher/rancher/security/advisories/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.
```shell
# 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](https://github.com/rancher/rancher/security/policy) for security related inquiries.
* Open an issue in [Rancher](https://github.com/rancher/rancher/issues/new/choose) repository.
* Verify our [support matrix](https://www.suse.com/suse-rancher/support-matrix/all-supported-versions/) and [product support lifecycle](https://www.suse.com/lifecycle/).
cves:
- CVE-2022-43755
ghsas:
- GHSA-8c69-r38j-rpfj