CVE-2026-59723 (CVSS 8.8)

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.

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CVSS v3.1 Score

8.8

HIGH

CVSS:3.1/AV:A/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H

EPSS — Exploit Prediction

0.0015

Probability of exploitation

0.04%

Percentile rank

EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.

Weakness Type (CWE)

CWE-346 CWE-346

References

Other 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

Frequently Asked Questions

What is CVE-2026-59723? +

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. It has a CVSS v3.1 base score of 8.8 (HIGH).

How severe is CVE-2026-59723? +

CVE-2026-59723 has a CVSS v3.1 score of 8.8 out of 10, rated HIGH. This is a high-severity vulnerability that should be prioritized for patching. The EPSS score is 0.0015, placing it in the 0th percentile for exploitation probability.

How do I check if I'm vulnerable to CVE-2026-59723? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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