CVE-2026-53522 json
Nezha Monitoring: Unbounded WebSocket Streams — Resource Exhaustion DoS
published 2026-06-12 4 mo ago modified 2026-10-25 14 d ago also GHSA-jg62-j5h6-8mpq , GO-2026-5831 , EUVD-2026-36601
- cvss
- 6.5
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.3%
- EPSS 0.3% chance of exploitation in 30 days, percentile 28%
- public exploits
- 0
- none known
Summary
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.
Patch / fix
- go github.com/nezhahq/nezha 2.2.0
- govulncheck-vulndb openSUSE Leap 16.0 0.0.20260723T184607-160000.1.1
opensuse advisories openSUSE-SU-2026:21483-1
CISA SSVC
- Exploitation
- Proof of concept is public
- Automatable
- no
- Technical impact
- partial
- Assessed
- 4 mo ago
Exploit prediction
0.35% chance of exploitation in the next 30 days, higher than 28% of all scored CVEs (FIRST EPSS, 2026-11-08).
Exploits and checks
- github.com https://github.com/nezhahq/nezha/security/advisories/GHSA-jg62-j5h6-8mpq referenced PoC, tagged "exploit" by a source, unverified
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 6.5 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H |
| GitHub | 3.1 | 6.5 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| go | github.com/nezhahq/nezha | >=1.0.0, <2.2.0 >=1.0.0 |
2.2.0 |
Affected products
- nezhahq nezha
Classification
- Weakness
-
- CWE-770 Allocation of Resources Without Limits or Throttling
References
-
github.com
/nezhahq/nezha/security/advisories/GHSA-jg62-j5h6-8mpq
exploit, web, advisory
-
nvd.nist.gov
/vuln/detail/CVE-2026-53522
advisory
-
github.com
/nezhahq/nezha
package
Sources
- CVE List CVE-2026-53522
- GitHub Advisory GHSA-jg62-j5h6-8mpq
- NVD CVE-2026-53522
- OSV GO-2026-5831
Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.