# CVE-2026-100555: OpenClaw before 2026.8.1 DNS Rebinding via attachment delivery

> An attacker can exploit DNS rebinding in attachment delivery to force the server to fetch private resources, leading to data disclosure.

- **Severity:** High 7.1 (`CVSS:4.0/AV:N/AC:H/AT:P/PR:L/UI:N/VC:H/VI:L/VA:N/SC:H/SI:L/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:** Yes
- **Published:** 26 Sep 2026
- **Updated:** 5 Oct 2026
- **Also known as:** GHSA-659j-39wf-988v, GHSA-cf95-m4jv-59rc, MINI-74cg-5hq6-fxcr

## What is CVE-2026-100555?

CVE-2026-100555 is a high-severity server-side request forgery vulnerability in OpenClaw, published on 26 Sep 2026. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

OpenClaw is an npm-distributed gateway application. In versions >= 2026.7.1 and < 2026.8.1, Synology Chat attachment delivery could lose DNS pinning: the Gateway validated a single DNS result for a supplied file URL but then passed the original hostname to the Synology NAS, where it could resolve to a different destination. When attachment delivery accepted a remotely influenced hostname, an attacker could use DNS rebinding to make the NAS fetch a private or otherwise policy-denied resource and return its contents to the addressed conversation (server-side request forgery). Practical impact depends on NAS routing, resolver behavior, and the response available at the private destination. The issue is fixed in 2026.8.1; as a workaround, disable remote URL attachment forwarding in Synology Chat.

Weakness: CWE-918 (Server-Side Request Forgery)

## Which versions are affected by CVE-2026-100555?


## How do I fix CVE-2026-100555?

Upgrade to a fixed version.

## Is CVE-2026-100555 being exploited?

There is no known exploitation of CVE-2026-100555 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-100555 and fix it if it is affected.

What it is: CVE-2026-100555 is a high-severity server-side request forgery vulnerability in OpenClaw, published on 26 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-2026-100555 in the wild and no public exploit code.

Affected product: OpenClaw. 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-2026-100555/ (Markdown: https://insights.sbomify.com/CVE-2026-100555/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-100555
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-100555
- OSV: https://osv.dev/vulnerability/CVE-2026-100555

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-100555/
Summaries are generated and may contain mistakes; the official description above is the record.