Quick answers
- Is CVE-2026-44211 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-44211 being exploited in the wild.
- How severe is CVE-2026-44211?
- Critical severity, with a CVSS score of 9.6, published 1 June 2026.
- Which products and versions are affected?
- Cline <= 0.1.59, <= 2.13.0; Cline Kanban <= 0.1.59; cline (npm) SEMVER:introduced=0,last_affected=2.13.0.
- Is there a fix for CVE-2026-44211?
- No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
- How is CVE-2026-44211 attacked?
- It is attacked over the network, in a software library.
- Am I affected by CVE-2026-44211?
- Check whether you run Cline, Cline Kanban or cline (npm) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.
Technical details
The vulnerability is a missing Origin header validation on three WebSocket endpoints in the kanban npm package: /api/runtime/ws (runtime state stream), /api/terminal/io (terminal input/output), and /api/terminal/control (task termination). Lacking both Origin validation and authentication, the server accepts and services connections from malicious cross-origin pages. Attack vector is network-based and requires user interaction (victim must visit an attacker-controlled webpage while Kanban is running). Upon connection, the runtime WebSocket immediately broadcasts workspace filesystem paths, task metadata, git information, and AI chat messages. The terminal I/O endpoint writes attacker-controlled bytes directly to the agent's pseudo-terminal, allowing arbitrary command injection with agent privileges. The terminal control endpoint accepts stop messages that terminate running tasks. A proof-of-concept demonstrates full exploitation including data exfiltration and remote code execution via terminal hijacking. No patches are currently available; recommended fixes include validating the Origin header, implementing session tokens, and requiring authentication on terminal endpoints.
Affected products
- Cline kanban 0.1.59 and earlier
Identifiers
- CVE-2026-44211
- GHSA-5c57-rqjx-35g2
Timeline
- 2026-05-08: disclosed
- 2026-05-08: advisory