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{"bugzilla": {"description": "github.com/nats-io/nats-server: NATS-Server: Denial of Service via malformed WebSockets frame", "id": "2451447", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2451447"}, "csaw": false, "cvss3": {"cvss3_base_score": "7.5", "cvss3_scoring_vector": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H", "status": "draft"}, "cwe": "CWE-1286", "details": ["A flaw was found in NATS-Server, a high-performance messaging system. A remote attacker can exploit this vulnerability before authentication by sending a specially crafted WebSockets frame. This missing sanity check can trigger a server panic, leading to a Denial of Service (DoS) for affected deployments that use WebSockets and expose the network port to untrusted endpoints."], "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-2026-27889", "package_state": [{"cpe": "cpe:/a:redhat:multicluster_globalhub", "fix_state": "Affected", "package_name": "multicluster-globalhub/multicluster-globalhub-grafana-rhel9", "product_name": "Multicluster Global Hub"}, {"cpe": "cpe:/a:redhat:openshift:4", "fix_state": "Affected", "package_name": "openshift4/oc-mirror-plugin-rhel9", "product_name": "Red Hat OpenShift Container Platform 4"}], "public_date": "2026-03-25T19:36:36Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-27889\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-27889\nhttps://advisories.nats.io/CVE/secnote-2026-03.txt\nhttps://github.com/nats-io/nats-server/security/advisories/GHSA-pq2q-rcw4-3hr6"], "threat_severity": "Important"}