CVE-2026-53522

MEDIUMPre-NVD 6.56.5—
EchelonGraph scoreMEDIUM confidence

This medium-severity CVE scores 6.5 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit probability: 0.3%, top 79% of all CVEs by exploit prediction. GitHub Security Advisory data not yet ingested — confidence will rise once GHSA publishes (typical lag: hours to days for open-source ecosystem CVEs; never for infrastructure-only CVEs).

Triggered by: NVD CVSS baseline
Sources: epss, secondary
6.5
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS: 0%CVSS: 6.5Exploit: NoneExposed: 0

No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.

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 v3
6.5
EG Score
6.5(medium)
EPSS
20.8%
KEV
Not listed

Published

June 12, 2026

Last Modified

June 15, 2026

Advisory Details (1)

Auto-updated Jun 12, 2026
🔬 Proof of concept available. Patch available. Sources: github.
github Patch Available🟡 PoC Available

Unbounded WebSocket Streams — Resource Exhaustion DoS · Advisory · nezhahq/nezha · GitHub

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

Vendor Advisories for CVE-2026-53522(1)

These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.

Weakness Classification(1)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

Data Freshness Timeline

(refreshed 14× in last 7d / 60× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.

  1. 2026-07-07 00:55 UTCEG score recompute
  2. 2026-07-06 16:27 UTCEPSS rescore
  3. 2026-07-06 16:27 UTCEPSS rescore
  4. 2026-07-06 02:23 UTCEPSS rescore
  5. 2026-07-06 02:23 UTCEPSS rescore
  6. 2026-07-05 09:35 UTCEG score recompute
  7. 2026-07-05 02:31 UTCEPSS rescore
  8. 2026-07-05 02:30 UTCEPSS rescore
  9. 2026-07-04 10:22 UTCEG score recompute
  10. 2026-07-03 04:12 UTCEG score recompute
  11. 2026-07-02 05:20 UTCEG score recompute
  12. 2026-07-01 15:07 UTCEPSS rescore
  13. 2026-07-01 06:31 UTCEG score recompute
  14. 2026-06-30 23:22 UTCEPSS rescore
  15. 2026-06-30 07:42 UTCEG score recompute
  16. 2026-06-29 14:06 UTCEPSS rescore
  17. 2026-06-29 14:06 UTCEPSS rescore
  18. 2026-06-29 08:49 UTCEG score recompute
  19. 2026-06-28 14:07 UTCEPSS rescore
  20. 2026-06-28 09:43 UTCEG score recompute
  21. 2026-06-28 04:56 UTCEPSS rescore
  22. 2026-06-28 04:56 UTCEPSS rescore
  23. 2026-06-27 10:53 UTCEG score recompute
  24. 2026-06-27 03:08 UTCEPSS rescore
  25. 2026-06-26 12:03 UTCEG score recompute
Show 35 more
  1. 2026-06-25 13:49 UTCEPSS rescore
  2. 2026-06-25 09:40 UTCEG score recompute
  3. 2026-06-24 14:05 UTCEPSS rescore
  4. 2026-06-24 10:51 UTCEG score recompute
  5. 2026-06-23 21:33 UTCEPSS rescore
  6. 2026-06-23 21:33 UTCEPSS rescore
  7. 2026-06-23 11:58 UTCEG score recompute
  8. 2026-06-22 14:25 UTCEPSS rescore
  9. 2026-06-22 14:25 UTCEPSS rescore
  10. 2026-06-22 13:08 UTCEG score recompute
  11. 2026-06-21 14:56 UTCEPSS rescore
  12. 2026-06-21 14:56 UTCEPSS rescore
  13. 2026-06-21 14:07 UTCEG score recompute
  14. 2026-06-21 01:59 UTCEPSS rescore
  15. 2026-06-21 01:59 UTCEPSS rescore
  16. 2026-06-20 13:35 UTCEG score recompute
  17. 2026-06-19 19:26 UTCEPSS rescore
  18. 2026-06-19 19:26 UTCEPSS rescore
  19. 2026-06-19 14:43 UTCEG score recompute
  20. 2026-06-18 17:52 UTCEPSS rescore
  21. 2026-06-18 17:52 UTCEPSS rescore
  22. 2026-06-18 15:48 UTCEG score recompute
  23. 2026-06-17 17:53 UTCEPSS rescore
  24. 2026-06-17 16:59 UTCEG score recompute
  25. 2026-06-16 17:53 UTCEPSS rescore
  26. 2026-06-16 17:41 UTCEG score recompute
  27. 2026-06-15 18:48 UTCEG score recompute
  28. 2026-06-15 17:49 UTCEPSS rescore
  29. 2026-06-15 17:49 UTCEPSS rescore
  30. 2026-06-14 23:18 UTCEPSS rescore
  31. 2026-06-14 19:57 UTCEG score recompute
  32. 2026-06-13 23:00 UTCEPSS rescore
  33. 2026-06-13 21:08 UTCEG score recompute
  34. 2026-06-12 22:18 UTCEG score recompute
  35. 2026-06-12 22:17 UTCNVD updatefirst tracked

Related CVEs(same CWE)

Frequently asked(5)

What is CVE-2026-53522?
CVE-2026-53522 is a medium vulnerability published on June 12, 2026. 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()…
When was CVE-2026-53522 disclosed?
CVE-2026-53522 was first published in the National Vulnerability Database on June 12, 2026, with the most recent update on June 15, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-53522 actively exploited?
CVE-2026-53522 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 20.8% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
What is the CVSS score of CVE-2026-53522?
CVE-2026-53522 has a CVSS v3 base score of 6.5 (NVD).
How do I remediate CVE-2026-53522?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-53522, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

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