{"id":"CVE-2026-58214","state":"PUBLISHED","title":"NATS Server: MQTT subscribe ACL bypass via $MQTT.deliver.pubrel prefix (incomplete fix for CVE-2026-33217)","description":"NATS Server is a high-performance server for NATS.io, the cloud and edge native messaging system. Prior to 2.14.3 and 2.12.12, an authenticated MQTT client could subscribe to the internal $MQTT.deliver.pubrel subject family, bypassing configured subscribe permissions and exposing MQTT QoS2 protocol metadata for sessions in the account. This issue is fixed in versions 2.14.3 and 2.12.12.","publishedAt":"2026-07-08T20:06:34.794Z","updatedAt":"2026-07-09T13:32:36.057Z","severity":{"score":4.3,"label":"Medium","version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N","source":"GitHub_M"},"assigner":"GitHub_M","products":["nats-io nats-server"],"affected":[{"vendor":"nats-io","product":"nats-server","versions":[{"version":"< 2.12.12","status":"affected"},{"version":">= 2.14.0-RC.1, < 2.14.3","status":"affected"}]}],"references":["https://github.com/nats-io/nats-server/security/advisories/GHSA-4g68-3pwx-5vfj","https://github.com/nats-io/nats-server/commit/297b166be60fe13144084eed4b25201ead03204a","https://github.com/nats-io/nats-server/commit/34b09657bb596d5f850eaa5cfc97ea6b2f989a97","https://github.com/nats-io/nats-server/releases/tag/v2.12.12","https://github.com/nats-io/nats-server/releases/tag/v2.14.3"],"weaknesses":["CWE-863"],"ingestedAt":"2026-10-29T20:12:24.861Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/58xxx/CVE-2026-58214.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-58214","state":"PUBLISHED","datePublished":"2026-07-08T20:06:34.794Z","dateUpdated":"2026-07-09T13:32:36.057Z","assignerShortName":"GitHub_M","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateReserved":"2026-06-29T17:09:25.873Z"},"containers":{"cna":{"title":"NATS Server: MQTT subscribe ACL bypass via $MQTT.deliver.pubrel prefix (incomplete fix for CVE-2026-33217)","descriptions":[{"lang":"en","value":"NATS Server is a high-performance server for NATS.io, the cloud and edge native messaging system. Prior to 2.14.3 and 2.12.12, an authenticated MQTT client could subscribe to the internal $MQTT.deliver.pubrel subject family, bypassing configured subscribe permissions and exposing MQTT QoS2 protocol metadata for sessions in the account. This issue is fixed in versions 2.14.3 and 2.12.12."}],"affected":[{"vendor":"nats-io","product":"nats-server","versions":[{"version":"< 2.12.12","status":"affected"},{"version":">= 2.14.0-RC.1, < 2.14.3","status":"affected"}]}],"references":[{"url":"https://github.com/nats-io/nats-server/security/advisories/GHSA-4g68-3pwx-5vfj","name":"https://github.com/nats-io/nats-server/security/advisories/GHSA-4g68-3pwx-5vfj","tags":["x_refsource_CONFIRM"]},{"url":"https://github.com/nats-io/nats-server/commit/297b166be60fe13144084eed4b25201ead03204a","name":"https://github.com/nats-io/nats-server/commit/297b166be60fe13144084eed4b25201ead03204a","tags":["x_refsource_MISC"]},{"url":"https://github.com/nats-io/nats-server/commit/34b09657bb596d5f850eaa5cfc97ea6b2f989a97","name":"https://github.com/nats-io/nats-server/commit/34b09657bb596d5f850eaa5cfc97ea6b2f989a97","tags":["x_refsource_MISC"]},{"url":"https://github.com/nats-io/nats-server/releases/tag/v2.12.12","name":"https://github.com/nats-io/nats-server/releases/tag/v2.12.12","tags":["x_refsource_MISC"]},{"url":"https://github.com/nats-io/nats-server/releases/tag/v2.14.3","name":"https://github.com/nats-io/nats-server/releases/tag/v2.14.3","tags":["x_refsource_MISC"]}],"metrics":[{"cvssV3_1":{"attackComplexity":"LOW","attackVector":"NETWORK","availabilityImpact":"NONE","baseScore":4.3,"baseSeverity":"MEDIUM","confidentialityImpact":"LOW","integrityImpact":"NONE","privilegesRequired":"LOW","scope":"UNCHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N","version":"3.1"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-863","lang":"en","description":"CWE-863: Incorrect Authorization","type":"CWE"}]}],"providerMetadata":{"shortName":"GitHub_M","orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateUpdated":"2026-07-08T20:06:34.794Z"},"source":{"advisory":"GHSA-4g68-3pwx-5vfj","discovery":"UNKNOWN"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-07-09T13:32:18.907165Z","id":"CVE-2026-58214","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-07-09T13:32:36.057Z"}}]}}}