# CVE-2026-59723: Cline: Cross-Origin WebSocket Hijacking in Cline Hub Dashboard (`/browser` endpoint)

> Attackers can hijack WebSocket connections to execute commands and modify settings if the local dashboard lacks a room secret.

- **Severity:** High 8.8 (`CVSS:3.1/AV:A/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Local or same network only
- **Victim action needed:** A user has to click or open something
- **Fix available:** Yes
- **Published:** 8 Jul 2026
- **Updated:** 10 Jul 2026
- **Also known as:** GHSA-3cj3-hqcr-g934

## What is CVE-2026-59723?

CVE-2026-59723 is a high-severity vulnerability in cline, published on 8 Jul 2026. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link.

### Official description

Cline is an autonomous coding agent as an SDK, IDE extension, or CLI assistant. Prior to 3.0.30, the Cline Hub dashboard server launched by the cline dashboard command accepts WebSocket connections on the /browser endpoint without validating the Origin header, and when ROOM_SECRET is unset for local 127.0.0.1 binds, isAuthorizedBrowserRequest() allows attacker-controlled websites to send desktopCommand frames that read workspace state, mutate MCP and provider settings, and trigger command execution when a provider or model is configured. This issue is fixed in version 3.0.30.

Weakness: CWE-346 (Origin Validation Error)

## Which versions are affected by CVE-2026-59723?

2 open source packages ship an affected version, including cline. It affects 1 product.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `cline` | npm | All versions | 3.0.30 |
| `cline` | npm | All versions | 3.0.30 |

Products: Cline Cline.

## How do I fix CVE-2026-59723?

Upgrade cline to 3.0.30 or later.

## Is CVE-2026-59723 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-59723 exists.

## Other vulnerabilities in cline

- [CVE-2026-30313](https://insights.sbomify.com/CVE-2026-30313/): Command injection in n/a (critical 9.8)
- [CVE-2026-44211](https://insights.sbomify.com/CVE-2026-44211/): Cline Kanban Server has a Cross-Origin WebSocket Hijacking Vulnerability (critical 9.6)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-59723 and fix it if it is affected.

What it is: CVE-2026-59723 is a high-severity vulnerability in cline, published on 8 Jul 2026. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-59723 exists.

Affected packages and fixed versions:
- cline (npm): affected all versions; fixed in 3.0.30
- cline (npm): affected all versions; fixed in 3.0.30

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-2026-59723/ (Markdown: https://insights.sbomify.com/CVE-2026-59723/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-59723
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-59723
- OSV: https://osv.dev/vulnerability/CVE-2026-59723

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-59723/
Summaries are generated and may contain mistakes; the official description above is the record.