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.
History

Mon, 15 Jun 2026 20:30:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'poc', 'Technical Impact': 'partial'}, 'version': '2.0.3'}


Sat, 13 Jun 2026 12:45:00 +0000

Type Values Removed Values Added
First Time appeared Nezhahq
Nezhahq nezha
Vendors & Products Nezhahq
Nezhahq nezha

Fri, 12 Jun 2026 21:45:00 +0000

Type Values Removed Values Added
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.
Title Nezha Monitoring: Unbounded WebSocket Streams — Resource Exhaustion DoS
Weaknesses CWE-770
References
Metrics cvssV3_1

{'score': 6.5, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H'}


cve-icon MITRE

Status: PUBLISHED

Assigner: GitHub_M

Published: 2026-06-12T21:04:38.357Z

Updated: 2026-06-15T19:27:20.840Z

Reserved: 2026-06-09T17:30:33.456Z

Link: CVE-2026-53522

cve-icon Vulnrichment

Updated: 2026-06-15T17:03:33.431Z

cve-icon NVD

Status : Deferred

Published: 2026-06-12T22:16:52.377

Modified: 2026-06-15T21:17:25.123

Link: CVE-2026-53522

cve-icon Redhat

No data.