CVE-2026-53522

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.

CVSS 3.1

6.5CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

EPSS

0.3% chance of exploitation in the next 30 days; higher than 21% of CVEs (scores of 2026-10-25)

CWE

CWE-770

Published

2026-06-12

Modified

2026-10-25

Record from

the NVD, synced 2026-10-25

Packages (OSV)

References

• https://github.com/nezhahq/nezha/security/advisories/GHSA-jg62-j5h6-8mpq
• https://github.com/nezhahq/nezha/security/advisories/GHSA-jg62-j5h6-8mpq

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