---
id: CVE-2026-62863
title: 'MoLing: unauthenticated SSE and wildcard CORS expose tool sessions'
summary: >-
  MoLing is a computer-use and browser-use based MCP server. Prior to 0.5.0,
  when MoLing runs in SSE mode using `-l`, its `/sse` and `/message` HTTP
  endpoints do not authenticate requests and the `mcp-go` dependency sets
  `Access-Control-Al…
severity: critical
cvss: 9.6
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:L'
cvssSource: cna
cwe:
  - CWE-942
  - CWE-306
vendor: gojue
product: moling
affected:
  - moling < 0.5.0
published: '2026-10-30'
updated: '2026-10-30'
sourceUpdated: '2026-10-30T20:33:14.561Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-62863'
references:
  - url: 'https://github.com/gojue/moling/security/advisories/GHSA-qpgh-hp5g-4vwp'
    label: 'https://github.com/gojue/moling/security/advisories/GHSA-qpgh-hp5g-4vwp'
  - url: 'https://github.com/gojue/moling/pull/48'
    label: 'https://github.com/gojue/moling/pull/48'
  - url: >-
      https://github.com/gojue/moling/commit/ae07f704cbc88d4419fc0fbaec278090fcd0502d
    label: >-
      https://github.com/gojue/moling/commit/ae07f704cbc88d4419fc0fbaec278090fcd0502d
  - url: 'https://github.com/gojue/moling/releases/tag/v0.5.0'
    label: 'https://github.com/gojue/moling/releases/tag/v0.5.0'
tags:
  - cve.org
epss: 0.00314
epssPercentile: 0.24402
ingestedAt: '2026-11-05T16:24:31.461Z'
---

## Overview

MoLing is a computer-use and browser-use based MCP server. Prior to 0.5.0, when MoLing runs in SSE mode using `-l`, its `/sse` and `/message` HTTP endpoints do not authenticate requests and the `mcp-go` dependency sets `Access-Control-Allow-Origin: *`. A malicious web page can open a cross-origin `EventSource` to `/sse`, including a loopback listener, and read the `endpoint` event to obtain `sessionId`. After a victim running SSE mode visits that page, the attacker can use the disclosed `sessionId` against `/message` to send unauthorized MCP tool calls. Depending on the configured tools, those calls can read or write local files, execute commands or perform other actions. Binding only to loopback does not prevent this browser-mediated attack. This issue is fixed in version 0.5.0.

## Affected

- `moling < 0.5.0`

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.