9.6
CRITICAL CVSS 3.1
CVE-2026-44211
Cline Kanban Server has a Cross-Origin WebSocket Hijacking Vulnerability
Description

Cline is an autonomous coding agent as an SDK, IDE extension, or CLI assistant. In versions 2.13.0 and prior, there is a cross-origin WebSocket hijack vulnerability in Cline Kanban servers. At time of publication, there are no publicly available patches.

INFO

Published Date :

June 1, 2026, 5:17 p.m.

Last Modified :

July 22, 2026, 7:10 a.m.

Remotely Exploit :

Yes !
Affected Products

The following products are affected by CVE-2026-44211 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

ID Vendor Product Action
1 Cline cline
CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 134c704f-9b21-4f2e-91b3-4a467353bcc0
CVSS 3.1 CRITICAL [email protected]
Solution
Address the cross-origin WebSocket hijack. Await vendor patch or implement mitigation.
  • Await vendor patch for Cline Kanban servers.
  • Consider implementing server-side WebSocket origin validation.
  • Restrict access to the Cline Kanban server.
  • Monitor server activity for suspicious connections.
Public PoC/Exploit Available at Github

CVE-2026-44211 has a 2 public PoC/Exploit available at Github. Go to the Public Exploits tab to see the list.

References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2026-44211.

URL Resource
https://github.com/cline/cline/security/advisories/GHSA-5c57-rqjx-35g2 Exploit Mitigation Vendor Advisory
https://github.com/cline/cline/security/advisories/GHSA-5c57-rqjx-35g2 Exploit Mitigation Vendor Advisory
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-44211 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

A curated timeline of real AI agent security incidents, breaches, and vulnerabilities (2024-2026). Every entry sourced and dated.

ai-agent-security ai-agents ai-security awesome-list cybersecurity llm-security mcp-security prompt-injection supply-chain-security adversarial-attacks agent-security agentic-ai ai-attacks ai-safety cve incident-response owasp red-team security-research vulnerability

Updated: 1 week, 3 days ago
37 stars 3 fork 3 watcher
Born at : April 7, 2026, 2:19 p.m. This repo has been linked 113 different CVEs too.

A deny-by-default contract & type-checker layer for AI agent tool calls — Pydantic-based, in-process, zero-core-deps. Validates the actual tool-call payload (ghost-arg stripping, strict types, self-healing retries) beneath MCP gateways & firewalls. Works with LangChain, OpenAI Agents SDK, PydanticAI & CrewAI.

ai-agents ai-security crewai firewall langchain llm-safety mcp-server openai pii-masking pydantic-ai python rbac sandbox tool-validation zero-trust

Python Makefile JavaScript HTML CSS Dockerfile

Updated: 6 days, 11 hours ago
10 stars 3 fork 3 watcher
Born at : Jan. 31, 2026, 8:43 a.m. This repo has been linked 23 different CVEs too.

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-44211 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-44211 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • CVE Translated by [email protected]

    Jul. 22, 2026

    Action Type Old Value New Value
    Added Translation Title: Cline Kanban Server, Description: Cline es un agente de codificación autónomo como un SDK, extensión de IDE o asistente de CLI. En las versiones 2.13.0 y anteriores, existe una vulnerabilidad de secuestro de WebSocket de origen cruzado en los servidores Kanban de Cline. En el momento de la publicación, no hay parches disponibles públicamente.
  • CVE Modified by [email protected]

    Jun. 17, 2026

    Action Type Old Value New Value
    Added Affected [{'vendor': 'cline', 'product': 'cline', 'versions': [{'status': 'affected', 'version': '<= 2.13.0'}]}]
  • CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0

    Jun. 17, 2026

    Action Type Old Value New Value
    Added SSVC {'id': 'CVE-2026-44211', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'poc'}, {'automatable': 'no'}, {'technicalImpact': 'total'}], 'version': '2.0.3', 'timestamp': '2026-06-03T00:00:00+00:00'}
  • Initial Analysis by [email protected]

    Jun. 03, 2026

    Action Type Old Value New Value
    Added CPE Configuration OR *cpe:2.3:a:cline:cline:*:*:*:*:*:*:*:* versions up to (including) 2.13.0
    Added Reference Type CISA-ADP: https://github.com/cline/cline/security/advisories/GHSA-5c57-rqjx-35g2 Types: Exploit, Mitigation, Vendor Advisory
    Added Reference Type GitHub, Inc.: https://github.com/cline/cline/security/advisories/GHSA-5c57-rqjx-35g2 Types: Exploit, Mitigation, Vendor Advisory
  • CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0

    Jun. 01, 2026

    Action Type Old Value New Value
    Added Reference https://github.com/cline/cline/security/advisories/GHSA-5c57-rqjx-35g2
  • New CVE Received by [email protected]

    Jun. 01, 2026

    Action Type Old Value New Value
    Added Description Cline is an autonomous coding agent as an SDK, IDE extension, or CLI assistant. In versions 2.13.0 and prior, there is a cross-origin WebSocket hijack vulnerability in Cline Kanban servers. At time of publication, there are no publicly available patches.
    Added CVSS V3.1 AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H
    Added CWE CWE-306
    Added CWE CWE-1385
    Added Reference https://github.com/cline/cline/security/advisories/GHSA-5c57-rqjx-35g2
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.