Threats tagged 'brew-mcp-atlassian-cve-2026-27124'

FastMCP OAuthProxy's callback handler does not verify that the browser sending the authorization code has just given consent, enabling a Confused Deputy vulnerability. An attacker can trick a victim's browser, already authorized with GitHub, into redirecting a valid authorization code to a malicious client. This allows the attacker to obtain an access token to the benign MCP server under the victim's GitHub account. The issue affects versions >=0.11.9 and <0.23.0 and is fixed in version 0.23.0.