# CVE-2026-86242: Unauthenticated RCE via Custom Plugin HTTP Path on Dynamically Linked Builds

> Unauthenticated attackers can achieve remote code execution on dynamically linked Bifrost builds by uploading malicious plugins via HTTP paths when management authentication is disabled.

- **Severity:** High 8.1 (`CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 6 Sep 2026
- **Updated:** 8 Sep 2026
- **Also known as:** GHSA-2qp8-4xgm-fw6g, GHSA-7g8f-4jrf-x782

## What is CVE-2026-86242?

CVE-2026-86242 is a high-severity code injection vulnerability in maximhq Bifrost, published on 6 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Bifrost HTTP transport before 2.0.0 accepts an enabled custom plugin whose path is an HTTP URL through unauthenticated POST /api/plugins when management authentication is disabled (the default, governance.auth_config.is_enabled=false). The shared-object loader treats an http-prefixed path as a download URL, writes the body to a temporary .so, and passes it to Go's plugin.Open. After a successful open, optional Init runs immediately with the supplied config as the Bifrost process user. On documented dynamically linked builds (DYNAMIC=1 / no static-link flags), which the vendor requires for custom Go plugins, plugin.Open is expected to succeed and this is unauthenticated remote code execution. On the published statically linked Docker image, plugin.Open fails with Dynamic loading not supported, so that build class is only server-side request forgery. Attack complexity is High because the attacker cannot force RCE on the default static image and a loadable plugin must match the host Go version, OS, architecture, and linkage. The 1.6.x HTTP transport line through 1.6.11 does not contain the fix.

Weakness: CWE-94 (Improper Control of Generation of Code), CWE-306 (Missing Authentication for Critical Functionality), CWE-284 (Improper Access Control)

## Which versions are affected by CVE-2026-86242?


## How do I fix CVE-2026-86242?

No fix has been published for CVE-2026-86242 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-86242 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-86242 exists.

Public exploit code:

- Bifrost < 1.6.3 - Unauthenticated Remote Plugin URL Fetch (nuclei): http/cves/2026/CVE-2026-86242.yaml

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-86242 and fix it if it is affected.

What it is: CVE-2026-86242 is a high-severity code injection vulnerability in maximhq Bifrost, published on 6 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-86242 exists.

Affected product: maximhq Bifrost. 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-2026-86242/ (Markdown: https://insights.sbomify.com/CVE-2026-86242/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-86242
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-86242
- OSV: https://osv.dev/vulnerability/CVE-2026-86242

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-86242/
Summaries are generated and may contain mistakes; the official description above is the record.