{"description":"Trending threats, MITRE ATT\u0026CK coverage, and detection metadata. Fed continuously.","favicon":"https://feed.craftedsignal.io/favicon-32x32.png","feed_url":"https://feed.craftedsignal.io/products/chatcli--1.215.2/feed.json","home_page_url":"https://feed.craftedsignal.io/","icon":"https://feed.craftedsignal.io/apple-touch-icon.png","items":[{"_cs_actors":[],"_cs_cpes":["cpe:2.3:a:chatcli:chatcli:*:*:*:*:*:*:*:*"],"_cs_cves":[{"cvss":8,"id":"CVE-2026-123271"}],"_cs_exploited":false,"_cs_has_poc":false,"_cs_poc_references":[],"_cs_products":["ChatCLI (\u003c 1.215.2)"],"_cs_severities":["high"],"_cs_tags":[],"_cs_type":"advisory","_cs_vendors":["ChatCLI"],"content_html":"\u003cp\u003eChatCLI versions before 1.215.2 contain an improper validation vulnerability in the Model Context Protocol (MCP) OAuth login flow. The application uses server-supplied Protected Resource Metadata as a resource indicator without verifying that it matches the locally configured server URL. An attacker operating a malicious MCP server can cause the application to request an OAuth bearer token for a different, potentially sensitive resource hosted on the same authorization server and subsequently replay that token to impersonate the user against that resource.\u003c/p\u003e\n\u003ch2 id=\"impact\"\u003eImpact\u003c/h2\u003e\n\u003cp\u003eSuccessful exploitation allows a malicious MCP server operator to obtain valid OAuth bearer tokens intended for different resources, leading to unauthorized access and user impersonation within the context of the shared authorization server.\u003c/p\u003e\n\u003ch2 id=\"recommendation\"\u003eRecommendation\u003c/h2\u003e\n\u003cul\u003e\n\u003cli\u003eUpgrade ChatCLI to version 1.215.2 or later immediately to patch the validation logic flaw.\u003c/li\u003e\n\u003cli\u003eReview OAuth authorization server logs for unusual token request patterns originating from MCP clients.\u003c/li\u003e\n\u003cli\u003eIn environments where upgrading is delayed, limit the use of MCP servers to trusted and verified sources.\u003c/li\u003e\n\u003c/ul\u003e\n","date_modified":"2026-11-05T20:30:19Z","date_published":"2026-11-05T20:30:19Z","id":"https://feed.craftedsignal.io/briefs/2026-11-chatcli-oauth-vulnerability/","summary":"ChatCLI versions prior to 1.215.2 are vulnerable to token theft and replay attacks because the application fails to validate Protected Resource Metadata during the MCP OAuth login flow.","title":"ChatCLI: Improper validation in MCP OAuth login flow (CVE-2026-123271)","url":"https://feed.craftedsignal.io/briefs/2026-11-chatcli-oauth-vulnerability/"}],"language":"en","title":"CraftedSignal Threat Feed - ChatCLI (\u003c 1.215.2)","version":"https://jsonfeed.org/version/1.1"}