# CVE-2026-10219: nextlevelbuilder GoClaw write_file Tool fsbridge.go FsBridge.WriteFile os command injection

> Remote attackers can execute arbitrary OS commands via the write_file tool in GoClaw, requiring a patch to mitigate the risk.

- **Severity:** Medium 6.9 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:P`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 1 Jun 2026
- **Updated:** 1 Jun 2026
- **Also known as:** GHSA-6jm8-4fhr-5w64, GO-2026-5951

## What is CVE-2026-10219?

CVE-2026-10219 is a medium-severity command injection vulnerability in nextlevelbuilder GoClaw, published on 1 Jun 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

A vulnerability was found in nextlevelbuilder GoClaw up to 3.11.3. This impacts the function FsBridge.WriteFile of the file internal/sandbox/fsbridge.go of the component write_file Tool. Performing a manipulation results in os command injection. The attack is possible to be carried out remotely. The exploit has been made public and could be used. The pull request to fix this issue awaits acceptance.

Weakness: CWE-78 (Improper Neutralization of Special Elements used in an OS Command), CWE-77 (Improper Neutralization of Special Elements used in a Command)

## Which versions are affected by CVE-2026-10219?

3 open source packages ship an affected version, including github.com/nextlevelbuilder/goclaw.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `github.com/nextlevelbuilder/goclaw` | Go | All versions | None |
| `github.com/nextlevelbuilder/goclaw` | Go | All versions to 3.11.3 | None |
| `github.com/nextlevelbuilder/goclaw` | Go | All versions to 3.11.3 | None |

## How do I fix CVE-2026-10219?

Apply the vendor's patch.

## Is CVE-2026-10219 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-10219 exists.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-10219 and fix it if it is affected.

What it is: CVE-2026-10219 is a medium-severity command injection vulnerability in nextlevelbuilder GoClaw, published on 1 Jun 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-2026-10219 exists.

Affected packages and fixed versions:
- github.com/nextlevelbuilder/goclaw (Go): affected all versions; no fix listed
- github.com/nextlevelbuilder/goclaw (Go): affected all versions up to 3.11.3; no fix listed
- github.com/nextlevelbuilder/goclaw (Go): affected all versions up to 3.11.3; no fix listed

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-2026-10219/ (Markdown: https://insights.sbomify.com/CVE-2026-10219/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-10219
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-10219
- OSV: https://osv.dev/vulnerability/CVE-2026-10219

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-10219/
Summaries are generated and may contain mistakes; the official description above is the record.