CVE-2026-27889

{"id": "CVE-2026-27889", "cveTags": [], "metrics": {"cvssMetricV31": [{"type": "Secondary", "source": "security-advisories@github.com", "cvssData": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 7.5, "attackVector": "NETWORK", "baseSeverity": "HIGH", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H", "integrityImpact": "NONE", "userInteraction": "NONE", "attackComplexity": "LOW", "availabilityImpact": "HIGH", "privilegesRequired": "NONE", "confidentialityImpact": "NONE"}, "impactScore": 3.6, "exploitabilityScore": 3.9}]}, "published": "2026-03-25T20:16:27.210", "references": [{"url": "https://advisories.nats.io/CVE/secnote-2026-03.txt", "tags": ["Mitigation", "Vendor Advisory"], "source": "security-advisories@github.com"}, {"url": "https://github.com/nats-io/nats-server/security/advisories/GHSA-pq2q-rcw4-3hr6", "tags": ["Mitigation", "Vendor Advisory"], "source": "security-advisories@github.com"}], "vulnStatus": "Analyzed", "weaknesses": [{"type": "Primary", "source": "security-advisories@github.com", "description": [{"lang": "en", "value": "CWE-190"}]}], "descriptions": [{"lang": "en", "value": "NATS-Server is a High-Performance server for NATS.io, a cloud and edge native messaging system. Starting in version 2.2.0 and prior to versions 2.11.14 and 2.12.5, a missing sanity check on a WebSockets frame could trigger a server panic in the nats-server. This happens before authentication, and so is exposed to anyone who can connect to the websockets port. Versions 2.11.14 and 2.12.5 contains a fix. A workaround is available. The vulnerability only affects deployments which use WebSockets and which expose the network port to untrusted end-points. If one is able to do so, a defense in depth of restricting either of these will mitigate the attack."}, {"lang": "es", "value": "NATS-Server es un servidor de alto rendimiento para NATS.io, un sistema de mensajer\u00eda nativo de la nube y del borde. A partir de la versi\u00f3n 2.2.0 y antes de las versiones 2.11.14 y 2.12.5, una comprobaci\u00f3n de cordura faltante en un marco de WebSockets podr\u00eda desencadenar un p\u00e1nico del servidor en el nats-server. Esto ocurre antes de la autenticaci\u00f3n, y por lo tanto est\u00e1 expuesto a cualquiera que pueda conectarse al puerto de websockets. Las versiones 2.11.14 y 2.12.5 contienen una correcci\u00f3n. Una soluci\u00f3n alternativa est\u00e1 disponible. La vulnerabilidad solo afecta a las implementaciones que usan WebSockets y que exponen el puerto de red a puntos finales no confiables. Si uno es capaz de hacerlo, una defensa en profundidad de restringir cualquiera de estos mitigar\u00e1 el ataque."}], "lastModified": "2026-03-26T17:13:16.140", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:a:linuxfoundation:nats-server:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "6681EAC6-5A1D-4F3A-926C-F7BEB21791AA", "versionEndExcluding": "2.11.14", "versionStartIncluding": "2.2.0"}, {"criteria": "cpe:2.3:a:linuxfoundation:nats-server:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "B141DA72-3502-4746-A246-EE1087C993F4", "versionEndExcluding": "2.12.5", "versionStartIncluding": "2.12.0"}], "operator": "OR"}]}], "sourceIdentifier": "security-advisories@github.com"}