# CVE-2026-75036: Fleet: DNS exfiltration via Sprig getHostByName in fleet.yaml Helm template preprocessing

> Attackers can exfiltrate cluster metadata and network information via DNS requests during Helm template preprocessing in Fleet.

- **Severity:** Medium 5.3 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 3 Sep 2026
- **Updated:** 5 Sep 2026
- **Also known as:** GHSA-x9m6-xcjr-hpjp

## What is CVE-2026-75036?

CVE-2026-75036 is a medium-severity server-side request forgery vulnerability in SUSE Fleet, published on 3 Sep 2026. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

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.

Weakness: CWE-918 (Server-Side Request Forgery), CWE-1336 (Improper Neutralization of Special Elements Used in a Template Engine)

## Which versions are affected by CVE-2026-75036?

It affects 1 product.


Products: Suse Rancher Fleet.

## How do I fix CVE-2026-75036?

No fix has been published for CVE-2026-75036 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-75036 being exploited?

There is no known exploitation of CVE-2026-75036 in the wild and no public exploit code.

## Other vulnerabilities in SUSE Fleet

- [CVE-2026-44935](https://insights.sbomify.com/CVE-2026-44935/): Rancher Fleet vulnerable to cross namespace secret disclosure via unvalidated `valuesFrom` references in Helm Deployer (critical 9.9)
- [CVE-2026-41050](https://insights.sbomify.com/CVE-2026-41050/): Helm impersonation bypass of `RESTClientGetter` retains `cluster-admin` during template rendering (critical 9.9)
- [CVE-2026-88808](https://insights.sbomify.com/CVE-2026-88808/): Privilege escalation in Rancher (high 8.8)
- [CVE-2026-44938](https://insights.sbomify.com/CVE-2026-44938/): Fleet has PSS Bypass through addLabelsFromOptions in Fleet Agent (high 8.8)
- [CVE-2026-44937](https://insights.sbomify.com/CVE-2026-44937/): SUSE Rancher Fleet had an Unauthenticated Webhook: Regex Injection via Unsanitized Repository URL Components (high 8.3)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-75036 and fix it if it is affected.

What it is: CVE-2026-75036 is a medium-severity server-side request forgery vulnerability in SUSE Fleet, published on 3 Sep 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-75036 in the wild and no public exploit code.

Affected product: SUSE Fleet. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-75036/ (Markdown: https://insights.sbomify.com/CVE-2026-75036/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-75036
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-75036
- OSV: https://osv.dev/vulnerability/CVE-2026-75036

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-75036/
Summaries are generated and may contain mistakes; the official description above is the record.