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TI-2026-65121 Aliases CVE-2026-101088GHSA-fqx6-jcw7-6879

Nezha before 2.3.1 Denial of Service via Concurrent Server Delete

Priority LOW 26CWE-367Published · Updated

Key facts

Attack vector
Network
Privileges required
Low
User interaction
None
Attack complexity
High
Attack requirements
Present
Impact type
—
Confidentiality · integrity · availability
None · None · High
Fix status
Fixed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA.

Summary

Nezha is a server and website monitoring tool. In versions >= 2.2.11 and < 2.3.1, the service sentinel worker (service/singleton/servicesentinel.go) contains an incomplete fix for a previously reported nil dereference denial of service (GHSA-qjpp-gffx-2wm9). The 2026-07-21 fix re-validated the service lifecycle under serviceResponseDataStoreLock but reused an already-captured, now stale reporter pointer and never re-validated the server, and that lock does not guard ServerShared. An authenticated user with the member role who owns an agent can issue a concurrent server delete (POST /api/v1/batch-delete/server) for their own server to win the race window, causing the worker to dereference a missing entry in the server list snapshot. Because the sentinel workers and the gRPC server have no recover()/recovery interceptor, the resulting panic is unrecovered and crashes the entire instance. This is fixed in version 2.3.1.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00182 7th percentileScored 2026-11-07
Fix Fixed nezha (nezhahq): 2.3.1

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
nezhahqnezha2.2.11 to before 2.3.12.3.1Patch availableCNA
  • nezha Vendornezhahq Affected 2.2.11 to before 2.3.1 Fixed in 2.3.1 Patch available CNA

Remediation

  • Fix · CNA nezha (nezhahq) Fixed in 2.3.1

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-101088
  2. 2026-10-03 Alias added: GHSA-fqx6-jcw7-6879

References

Advisory 1

  • TI-2026-65123 Nezha through 2.2.3 Host Header Injection via OAuth2 redirect_uri CVSS 4.0CRITICAL 9.3
  • TI-2026-34341 Nezha Monitoring: RoleMember can run shell on every server (cross-tenant RCE) via POST /api/v1/cron CVSS 3.1CRITICAL 9.9
  • TI-2026-34342 Nezha Monitoring: RoleMember-reachable SSRF with full response-body reflection via POST /api/v1/notification CVSS 3.1HIGH 7.7
  • TI-2026-38597 Nezha Monitoring: OAuth2 Redirect URL — Host Header Injection CVSS 3.1MEDIUM 6.8
  • TI-2026-75131 Memory exhaustion in Nezha file manager WebSocket endpoint CVSS 4.0HIGH 7.1
  • TI-2026-75130 Nezha WebSocket transfer endpoint flaw enables denial of service CVSS 4.0HIGH 7.1
See all 29 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences