GHSA-8w87-58w6-hfv8 CVE-2021-36783
Rancher doesn't properly sanitize credentials in cluster template answers
- Severity
- 9.9 / 10
- Critical · CVSS 3.1
- Exploit chance (EPSS)
- 0.78%
- Chance of exploitation in the next 30 days. Higher than 55.90% of scored vulnerabilities.
- Known exploited
- No
- Not in CISA's catalog
- Weakness
- CWE-200 Exposure of Sensitive Information to an Unauthorized Actor
- CWE-312 Cleartext Storage of Sensitive Information
- CWE-522 Insufficiently Protected Credentials
- Fix
2.5.13- Upgrade github.com/rancher/rancher to this version or later
Description
Impact
It was discovered that in Rancher versions up to and including 2.5.12 and 2.6.3 there is a failure to properly sanitize credentials in cluster template answers. This failure can lead to plaintext storage and exposure of credentials, passwords and API tokens.
The exposed credentials are visible in Rancher to authenticated Cluster Owners, Cluster Members, Project Owners and Project Members on the endpoints /v1/management.cattle.io.clusters, /v3/clusters and /k8s/clusters/local/apis/management.cattle.io/v3/clusters.
Sensitive fields are now stripped from Clusters objects before the object is stored. For objects that existed before this security fix, a one-time migration happens on startup.
Important:
- It is highly advised to review for potential leaked credentials in this scenario, and to change them if deemed necessary.
- The final impact severity for confidentiality, integrity and availability is dependent on the permissions that the leaked credentials have on their own services.
Patches
Patched versions include releases 2.5.13, 2.6.4 and later versions.
Workarounds
Limit access in Rancher to trusted users. There is not a direct mitigation besides upgrading to the patched Rancher versions.
Important: It is highly advised to review for potential leaked credentials in this scenario, and to change them if deemed necessary.
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 versions
Go
| Package | Vulnerable | Fixed in |
|---|---|---|
| github.com/rancher/rancher | >= 2.5.0, < 2.5.13 |
2.5.13 |
| github.com/rancher/rancher | >= 2.6.0, < 2.6.4 |
2.6.4 |
How to fix
Move to the fixed version or later with your package manager, update the lockfile, and run your tests. If the package only arrives through another dependency, upgrade that dependency first. If none of its releases pulls a fixed version yet, force the version with your package manager's override.
github.com/rancher/rancher Go → 2.5.13
- go
go get github.com/rancher/rancher@v2.5.13 && go mod tidy
Severity breakdown
CVSS 3.1 9.9
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
- Attack vector
- Network
- Attack complexity
- Low
- Privileges required
- Low
- User interaction
- None
- Scope
- Changed
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Weakness
CWE-200: Exposure of Sensitive Information to an Unauthorized Actor
The product exposes sensitive information to an actor that is not explicitly authorized to have access to that information.
How to prevent it
- Architecture and Design: Compartmentalize the system to have "safe" areas where trust boundaries can be unambiguously drawn. Do not allow sensitive data to go outside of the trust boundary and always be careful when interfacing with a compartment outside of the safe area. Ensure that appropriate compartmentalization is built into the system design, and the compartmentalization allows for and reinforces privilege separation functionality. Architects and designers should rely on the principle of least privilege to decide the appropriate time to use privileges and the time to drop privileges.
CWE-312: Cleartext Storage of Sensitive Information
The product stores sensitive information in cleartext within a resource that might be accessible to another control sphere.
How to prevent it
- Implementation, System Configuration, Operation: When storing data in the cloud (e.g., S3 buckets, Azure blobs, Google Cloud Storage, etc.), use the provider's controls to encrypt the data at rest. [REF-1297] [REF-1299] [REF-1301]
- Implementation, System Configuration, Operation: In some systems/environments such as cloud, the use of "double encryption" (at both the software and hardware layer) might be required, and the developer might be solely responsible for both layers, instead of shared responsibility with the administrator of the broader system/environment.
CWE-522: Insufficiently Protected Credentials
The product transmits or stores authentication credentials, but it uses an insecure method that is susceptible to unauthorized interception and/or retrieval.
How to prevent it
- Architecture and Design: Use an appropriate security mechanism to protect the credentials.
- Architecture and Design: Make appropriate use of cryptography to protect the credentials.
- Implementation: Use industry standards to protect the credentials (e.g. LDAP, keystore, etc.).
References
Advisories
Packages
Other links
Timeline
- Published
- Last updated by the source
- Latest EPSS score
Related advisories
| Advisory | Severity | Why it's related |
|---|---|---|
| GHSA-4j6x-2764-m8gh Rancher has over-inclusive team membership expansion in GitHub App authentication provider | High | Also affects github.com/rancher/rancher |
| GHSA-vx8h-4prv-g744 Rancher has Privilege Escalation from Project Owner to Host | High | Also affects github.com/rancher/rancher |
| GHSA-mhc6-2gfq-xx62 Rancher vulnerable to command injection through unsanitized YAML parameter | Critical | Also affects github.com/rancher/rancher |
| GHSA-5v3h-x4wf-5c35 Rancher Extensions have arbitrary file access via path traversal | High | Also affects github.com/rancher/rancher |
| GHSA-gqf8-rvrh-g7w6 Rancher cloud credentials can be used through proxy API by users without access | Critical | Also affects github.com/rancher/rancher |
| GHSA-hwm2-4ph6-w6m5 Rancher's restricted PodSecurityPolicy does not prevent containers from running as a privileged user | High | Also affects github.com/rancher/rancher |
| GHSA-mc24-7m59-4q5p Rancher CLI skips TLS verification on Rancher CLI login command | Medium | Also affects github.com/rancher/rancher |
| GHSA-mw39-9qc2-f7mg Rancher exposes sensitive information through audit logs | Medium | Also affects github.com/rancher/rancher |
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