CVE-2023-32198 — steve
HIGHCVE-2023-32198 is a high-severity (CVSS 8) vulnerability in github.com/rancher/steve. A fix is available for github.com/rancher/steve — see the affected versions and patch details below.
Steve doesn’t verify a server’s certificate and is susceptible to man-in-the-middle (MitM) attacks
Real-World Exposure
github.com/rancher/steve🐹github.com/rancher/steve🐹github.com/rancher/steve🐹github.com/rancher/steveReal-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 in Steve where by default it was using an insecure option that did not validate the certificate presented by the remote server while performing a TLS connection. This could allow the execution of a man-in-the-middle (MitM) attack against services using Steve.
For example, Rancher relies on Steve as a dependency for its user interface (UI) to proxy requests to Kubernetes clusters. Users who have the permission to create a service in Rancher’s local cluster can take over Rancher’s UI and display their own UI to gather sensitive information. This is only possible when the setting ui-offline-preferred is manually set to remote (by default Rancher sets it to dynamic). This enables further attacks such as cross-site scripting (XSS), or tampering the UI to collect passwords from other users etc.
Please consult the associated MITRE ATT&CK - Technique - Adversary-in-the-Middle for further information about this category of attack.
Patches
Patched versions of Steve include releases v0.2.1, v0.3.3, v0.4.4 and v0.5.13.
This vulnerability is addressed by changing Steve to always verify a server’s certificate based on Go’s TLS settings.
Workarounds
If you can't upgrade to a fixed version, please make sure that you are only using Steve to connect to trusted servers.
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/steve | ≥ 0.2.0&&< 0.2.1 | 0.2.1go get github.com/rancher/steve@v0.2.1 |
| 🐹Go | github.com/rancher/steve | ≥ 0.3.0&&< 0.3.3 | 0.3.3go get github.com/rancher/steve@v0.3.3 |
| 🐹Go | github.com/rancher/steve | ≥ 0.4.0&&< 0.4.4 | 0.4.4go get github.com/rancher/steve@v0.4.4 |
| 🐹Go | github.com/rancher/steve | ≥ 0.5.0&&< 0.5.13 | 0.5.13go get github.com/rancher/steve@v0.5.13 |
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/steve, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update github.com/rancher/steve to 0.2.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2023-32198 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 CVE-2023-32198 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2023-32198. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2023-32198 in your dependencies?
O3 Security finds CVE-2023-32198 across Go dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.