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{"bugzilla": {"description": "github.com/mark3labs/mcp-go: mcp-go: DNS Rebinding vulnerability due to missing Host header validation", "id": "2525106", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2525106"}, "csaw": false, "cvss3": {"cvss3_base_score": "6.8", "cvss3_scoring_vector": "CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:N", "status": "draft"}, "cwe": "CWE-918", "details": ["A flaw was found in mcp-go. This component failed to validate the Host header in HTTP requests, specifically within its StreamableHTTPServer and SSEServer transports. A remote attacker could exploit this by using a crafted web page to perform a DNS rebinding attack. This allows the attacker to direct a controlled domain name to the loopback address, bypassing local network restrictions. Consequently, the attacker could access and interact with local services and resources, potentially leading to information disclosure or unauthorized actions."], "name": "CVE-2026-81092", "package_state": [{"cpe": "cpe:/a:redhat:connectivity_link:1", "fix_state": "Fix deferred", "package_name": "rhcl-tech-preview/mcp-gateway-rhel9", "product_name": "Red Hat Connectivity Link 1"}, {"cpe": "cpe:/a:redhat:connectivity_link:1", "fix_state": "Fix deferred", "package_name": "rhcl-tech-preview/mcp-gateway-rhel9-operator", "product_name": "Red Hat Connectivity Link 1"}, {"cpe": "cpe:/a:redhat:hummingbird:1", "fix_state": "Affected", "package_name": "tempo2.10", "product_name": "Red Hat Hardened Images"}, {"cpe": "cpe:/a:redhat:hummingbird:1", "fix_state": "Affected", "package_name": "tempo3.0", "product_name": "Red Hat Hardened Images"}, {"cpe": "cpe:/a:redhat:openshift_ai", "fix_state": "Fix deferred", "package_name": "rhoai/rhai-cli-rhel9", "product_name": "Red Hat OpenShift AI (RHOAI)"}, {"cpe": "cpe:/a:redhat:openshift_distributed_tracing:3", "fix_state": "Fix deferred", "package_name": "rhosdt/tempo-query-rhel9", "product_name": "Red Hat OpenShift distributed tracing 3"}, {"cpe": "cpe:/a:redhat:openshift_distributed_tracing:3", "fix_state": "Fix deferred", "package_name": "rhosdt/tempo-rhel9", "product_name": "Red Hat OpenShift distributed tracing 3"}], "public_date": "2026-08-27T14:50:33Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-81092\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-81092\nhttps://github.com/mark3labs/mcp-go\nhttps://github.com/mark3labs/mcp-go/pull/921\nhttps://github.com/mark3labs/mcp-go/releases/tag/v0.56.0\nhttps://www.vulncheck.com/advisories/mcp-go-before-0.56.0-missing-host-header-validation-enables-dns-rebinding"], "threat_severity": "Moderate"}