Skip to content

Steve doesn’t verify a server’s certificate and is susceptible to man-in-the-middle (MitM) attacks

High severity GitHub Reviewed Published Apr 25, 2025 in rancher/steve • Updated Apr 25, 2025

Package

gomod github.com/rancher/stev (Go)

Affected versions

>= 0.3.0, < 0.3.3

Patched versions

0.3.3
gomod github.com/rancher/steve (Go)
>= 0.2.0, < 0.2.1
>= 0.4.0, < 0.4.4
>= 0.5.0, < 0.5.13
0.2.1
0.4.4
0.5.13

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:

References

@pdellamore pdellamore published to rancher/steve Apr 25, 2025
Published to the GitHub Advisory Database Apr 25, 2025
Reviewed Apr 25, 2025
Last updated Apr 25, 2025

Severity

High

CVSS overall score

This score calculates overall vulnerability severity from 0 to 10 and is based on the Common Vulnerability Scoring System (CVSS).
/ 10

CVSS v3 base metrics

Attack vector
Network
Attack complexity
High
Privileges required
High
User interaction
None
Scope
Changed
Confidentiality
High
Integrity
High
Availability
High

CVSS v3 base metrics

Attack vector: More severe the more the remote (logically and physically) an attacker can be in order to exploit the vulnerability.
Attack complexity: More severe for the least complex attacks.
Privileges required: More severe if no privileges are required.
User interaction: More severe when no user interaction is required.
Scope: More severe when a scope change occurs, e.g. one vulnerable component impacts resources in components beyond its security scope.
Confidentiality: More severe when loss of data confidentiality is highest, measuring the level of data access available to an unauthorized user.
Integrity: More severe when loss of data integrity is the highest, measuring the consequence of data modification possible by an unauthorized user.
Availability: More severe when the loss of impacted component availability is highest.
CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:C/C:H/I:H/A:H

EPSS score

Weaknesses

CVE ID

CVE-2023-32198

GHSA ID

GHSA-95fc-g4gj-mqmx

Source code

Loading Checking history
See something to contribute? Suggest improvements for this vulnerability.