{"id":"CVE-2026-53522","state":"PUBLISHED","title":"Nezha Monitoring: Unbounded WebSocket Streams — Resource Exhaustion DoS","description":"Nezha Monitoring is a self-hostable, lightweight, servers and websites monitoring and O&M tool. From version 1.0.0 to before version 2.2.0, the Nezha dashboard exposes two endpoints that create long-lived WebSocket streams to monitored agents: POST /api/v1/terminal → createTerminal() (terminal.go:27-67) and POST /api/v1/file → createFM() (fm.go:28-67). Both call rpc.NezhaHandlerSingleton.CreateStream(streamId, ...) which inserts a new ioStreamContext into an unbounded map[string]*ioStreamContext (s.ioStreams in io_stream.go:59-67). There is no per-user rate limit, no global semaphore, and no per-server connection cap. This issue has been patched in version 2.2.0.","publishedAt":"2026-06-12T21:04:38.357Z","updatedAt":"2026-06-15T19:27:20.840Z","severity":{"score":6.5,"label":"Medium","version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","source":"GitHub_M"},"assigner":"GitHub_M","products":["nezhahq nezha"],"affected":[{"vendor":"nezhahq","product":"nezha","versions":[{"version":">= 1.0.0, < 2.2.0","status":"affected"}]}],"references":["https://github.com/nezhahq/nezha/security/advisories/GHSA-jg62-j5h6-8mpq"],"weaknesses":["CWE-770"],"ingestedAt":"2026-10-29T20:12:16.098Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/53xxx/CVE-2026-53522.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-53522","state":"PUBLISHED","datePublished":"2026-06-12T21:04:38.357Z","dateUpdated":"2026-06-15T19:27:20.840Z","assignerShortName":"GitHub_M","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateReserved":"2026-06-09T17:30:33.456Z"},"containers":{"cna":{"title":"Nezha Monitoring: Unbounded WebSocket Streams — Resource Exhaustion DoS","descriptions":[{"lang":"en","value":"Nezha Monitoring is a self-hostable, lightweight, servers and websites monitoring and O&M tool. From version 1.0.0 to before version 2.2.0, the Nezha dashboard exposes two endpoints that create long-lived WebSocket streams to monitored agents: POST /api/v1/terminal → createTerminal() (terminal.go:27-67) and POST /api/v1/file → createFM() (fm.go:28-67). Both call rpc.NezhaHandlerSingleton.CreateStream(streamId, ...) which inserts a new ioStreamContext into an unbounded map[string]*ioStreamContext (s.ioStreams in io_stream.go:59-67). There is no per-user rate limit, no global semaphore, and no per-server connection cap. This issue has been patched in version 2.2.0."}],"affected":[{"vendor":"nezhahq","product":"nezha","versions":[{"version":">= 1.0.0, < 2.2.0","status":"affected"}]}],"references":[{"url":"https://github.com/nezhahq/nezha/security/advisories/GHSA-jg62-j5h6-8mpq","name":"https://github.com/nezhahq/nezha/security/advisories/GHSA-jg62-j5h6-8mpq","tags":["x_refsource_CONFIRM"]}],"metrics":[{"cvssV3_1":{"attackComplexity":"LOW","attackVector":"NETWORK","availabilityImpact":"HIGH","baseScore":6.5,"baseSeverity":"MEDIUM","confidentialityImpact":"NONE","integrityImpact":"NONE","privilegesRequired":"LOW","scope":"UNCHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","version":"3.1"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-770","lang":"en","description":"CWE-770: Allocation of Resources Without Limits or Throttling","type":"CWE"}]}],"providerMetadata":{"shortName":"GitHub_M","orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateUpdated":"2026-06-12T21:04:38.357Z"},"source":{"advisory":"GHSA-jg62-j5h6-8mpq","discovery":"UNKNOWN"}},"adp":[{"title":"CISA ADP Vulnrichment","references":[{"url":"https://github.com/nezhahq/nezha/security/advisories/GHSA-jg62-j5h6-8mpq","tags":["exploit"]}],"metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-06-15T17:03:17.090512Z","id":"CVE-2026-53522","options":[{"Exploitation":"poc"},{"Automatable":"no"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-06-15T19:27:20.840Z"}}]}}}