{"id":"DEBIAN-CVE-2026-27889","details":"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.","modified":"2026-09-10T08:47:33.176308519Z","published":"2026-03-25T20:16:27.210Z","upstream":["CVE-2026-27889"],"references":[{"type":"ADVISORY","url":"https://security-tracker.debian.org/tracker/CVE-2026-27889"}],"affected":[{"package":{"name":"nats-server","ecosystem":"Debian:12","purl":"pkg:deb/debian/nats-server?arch=source&distro=bookworm"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2.10.1-1","2.10.16-1","2.10.18-1","2.10.24-1","2.10.27-1","2.10.3-1","2.10.4-1","2.10.7-1","2.12.4-1","2.12.6-1","2.14.1-1","2.14.3-1","2.9.10-1","2.9.19-1"],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2026-27889.json"}},{"package":{"name":"nats-server","ecosystem":"Debian:13","purl":"pkg:deb/debian/nats-server?arch=source&distro=trixie"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2.10.27-1","2.12.4-1","2.12.6-1","2.14.1-1","2.14.3-1"],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2026-27889.json"}},{"package":{"name":"nats-server","ecosystem":"Debian:14","purl":"pkg:deb/debian/nats-server?arch=source&distro=forky"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2.12.6-1"}]}],"versions":["2.10.27-1","2.12.4-1"],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2026-27889.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"}]}