Nezha before 2.3.1 Denial of Service via Concurrent Server Delete
Published Sep 27, 2026
6.0
MEDIUMCVSS 4.0
EPSS 0.18%
Description
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.
Affected products
-
- Version 2.2.11StatusaffectedConstraints<2.3.1
- Version 2.3.1StatusunaffectedConstraints-
- Version
No data.
No data.
No Red Hat product state for this CVE.
No package ranges for this CVE.
Remediation
No remediation recorded yet.
References (3)
- https://euvd.enisa.europa.eu/vulnerability/EUVD-2026-88023 Advisory
- https://github.com/nezhahq/nezha/security/advisories/GHSA-jx78-55p5-rwv5 vendor-advisory
- https://www.vulncheck.com/advisories/nezha-before-2.3.1-denial-of-service-via-concurrent-server-delete third-party-advisory
| Link | Providers | Tags |
|---|---|---|
| https://euvd.enisa.europa.eu/vulnerability/EUVD-2026-88023 | Advisory | |
| https://github.com/nezhahq/nezha/security/advisories/GHSA-jx78-55p5-rwv5 | vendor-advisory | |
| https://www.vulncheck.com/advisories/nezha-before-2.3.1-denial-of-service-via-concurrent-server-delete | third-party-advisory |
Change history (0)
No recorded changes yet.