CVE-2026-64684

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{"bugzilla": {"description": "rmcp: RMCP: Sensitive HTTP headers leaked during cross-origin redirects", "id": "2535732", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2535732"}, "csaw": false, "cvss3": {"cvss3_base_score": "6.8", "cvss3_scoring_vector": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:N/A:N", "status": "draft"}, "cwe": "CWE-212", "details": ["A flaw was found in the `rmcp` component. This vulnerability allows a remote attacker to disclose sensitive information. When the `rmcp` crate's HTTP client processes a redirect to a different web address (cross-origin redirect) from a malicious or compromised Model Context Protocol (MCP) endpoint, it can inadvertently replay custom HTTP headers, such as API keys or authentication tokens, to the new, untrusted destination. This enables an attacker to capture and potentially reuse these sensitive credentials."], "mitigation": {"lang": "en:us", "value": "Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability."}, "name": "CVE-2026-64684", "package_state": [{"cpe": "cpe:/o:redhat:enterprise_linux:10", "fix_state": "Fix deferred", "package_name": "goose", "product_name": "Red Hat Enterprise Linux 10"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Fix deferred", "package_name": "goose", "product_name": "Red Hat Enterprise Linux 9"}], "public_date": "2026-09-16T21:18:48Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-64684\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-64684\nhttps://github.com/modelcontextprotocol/rust-sdk/commit/496902b9cf2c8a947454718da31829ae776b969b\nhttps://github.com/modelcontextprotocol/rust-sdk/pull/936\nhttps://github.com/modelcontextprotocol/rust-sdk/releases/tag/rmcp-v2.1.0\nhttps://github.com/modelcontextprotocol/rust-sdk/security/advisories/GHSA-9g45-5xwm-f3wc"], "threat_severity": "Moderate"}

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