What’s Vulnerable › Vulnerabilities

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

• Severity: high (CVSS 8.8 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.2% probability of exploitation in the next 30 days
• Public exploit or detection template: yes
• Published: 2026-07-08 · updated 2026-08-26
• Weakness: CWE-346

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.

Affected products

• cline: before 3.0.30 — fixed in 3.0.30

How to fix

Upgrade to a fixed version: cline 3.0.30. Check the vendor advisory for mitigations.

References

• https://github.com/cline/cline/commit/d09270940f5746f288cfc4a5039b46a2f4d5d01e
• https://github.com/cline/cline/pull/11724
• https://github.com/cline/cline/releases/tag/cli-v3.0.30
• https://github.com/cline/cline/security/advisories/GHSA-3cj3-hqcr-g934
• https://github.com/cline/cline/security/advisories/GHSA-3cj3-hqcr-g934

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