Rancher Fleet up to 0.16.0 Helm Template Preprocessing information disclosure

Summaryinfo

A vulnerability was found in Rancher Fleet up to 0.12.18/0.13.14/0.14.9/0.15.5/0.16.0. It has been classified as problematic. The affected element is an unknown function of the component Helm Template Preprocessing. The manipulation leads to information disclosure. This vulnerability is traded as CVE-2026-75036. It is possible to initiate the attack remotely. There is no exploit available.

Detailsinfo

A vulnerability, which was classified as problematic, has been found in Rancher Fleet up to 0.12.18/0.13.14/0.14.9/0.15.5/0.16.0. This issue affects an unknown code block of the component Helm Template Preprocessing. The manipulation with an unknown input leads to a information disclosure vulnerability. Using CWE to declare the problem leads to CWE-200. The product exposes sensitive information to an actor that is not explicitly authorized to have access to that information. Impacted is confidentiality. The summary by CVE is:

A security vulnerability was discovered in Fleet's Helm template preprocessing where templates evaluated by the Fleet controller could reach network resources outside the management cluster. A user who can supply bundle content to a repository referenced by a `GitRepo` resource can cause the Fleet controller to: - Disclose cluster metadata available to the templating context. - Reveal information about hosts reachable from the controller's network position. Because the disclosure channel is name resolution, it may remain effective in environments where outbound traffic is otherwise restricted. The disclosed information is limited to values exposed to the Fleet templating context and to name resolution results. Integrity and availability of managed clusters are not affected. This issue affects Fleet: from 0.12.0 before 0.12.19, from 0.13.0 before 0.13.15, from 0.14.0 before 0.14.10, from 0.15.0 before 0.15.6, and from 0.16.0 before 0.16.1.

It is possible to read the advisory at github.com. The identification of this vulnerability is CVE-2026-75036 since 08/17/2026. The exploitation is known to be easy. The attack may be initiated remotely. The technical details are unknown and an exploit is not publicly available. The attack technique deployed by this issue is T1592 according to MITRE ATT&CK.

Upgrading to version 0.12.19, 0.13.15, 0.14.10, 0.15.6 or 0.16.1 eliminates this vulnerability.

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Productinfo

Vendor

• Rancher

Name

• Fleet

Version

• 0.1
• 0.2
• 0.3
• 0.4
• 0.5
• 0.6
• 0.7
• 0.8
• 0.9
• 0.10
• 0.11
• 0.12
• 0.12.0
• 0.12.1
• 0.12.2
• 0.12.3
• 0.12.4
• 0.12.5
• 0.12.6
• 0.12.7
• 0.12.8
• 0.12.9
• 0.12.10
• 0.12.11
• 0.12.12
• 0.12.13
• 0.12.14
• 0.12.15
• 0.12.16
• 0.12.17
• 0.12.18
• 0.13
• 0.13.0
• 0.13.1
• 0.13.2
• 0.13.3
• 0.13.4
• 0.13.5
• 0.13.6
• 0.13.7
• 0.13.8
• 0.13.9
• 0.13.10
• 0.13.11
• 0.13.12
• 0.13.13
• 0.13.14
• 0.14
• 0.14.0
• 0.14.1
• 0.14.2
• 0.14.3
• 0.14.4
• 0.14.5
• 0.14.6
• 0.14.7
• 0.14.8
• 0.14.9
• 0.15
• 0.15.0
• 0.15.1
• 0.15.2
• 0.15.3
• 0.15.4
• 0.15.5
• 0.16.0

Website

• Product: https://github.com/rancher/fleet/

CPE 2.3info

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