{"id":"CVE-2026-53522","sourceIdentifier":"security-advisories@github.com","published":"2026-06-12T22:16:52.377","lastModified":"2026-06-17T10:57:57.747","vulnStatus":"Deferred","cveTags":[],"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":[{"source":"security-advisories@github.com","affectedData":[{"vendor":"nezhahq","product":"nezha","versions":[{"version":">= 1.0.0, < 2.2.0","status":"affected"}]}]}],"metrics":{"cvssMetricV31":[{"source":"security-advisories@github.com","type":"Secondary","cvssData":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","baseScore":6.5,"baseSeverity":"MEDIUM","attackVector":"NETWORK","attackComplexity":"LOW","privilegesRequired":"LOW","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"NONE","integrityImpact":"NONE","availabilityImpact":"HIGH"},"exploitabilityScore":2.8,"impactScore":3.6}],"ssvcV203":[{"source":"134c704f-9b21-4f2e-91b3-4a467353bcc0","ssvcData":{"timestamp":"2026-06-15T17:03:17.090512Z","id":"CVE-2026-53522","options":[{"exploitation":"poc"},{"automatable":"no"},{"technicalImpact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}]},"weaknesses":[{"source":"security-advisories@github.com","type":"Secondary","description":[{"lang":"en","value":"CWE-770"}]}],"references":[{"url":"https://github.com/nezhahq/nezha/security/advisories/GHSA-jg62-j5h6-8mpq","source":"security-advisories@github.com"},{"url":"https://github.com/nezhahq/nezha/security/advisories/GHSA-jg62-j5h6-8mpq","source":"134c704f-9b21-4f2e-91b3-4a467353bcc0"}]}