CVE-2026-101088Nezha before 2.3.1 Denial of Service via Concurrent Server Delete

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.

CVSS

5.3 MEDIUM (v3.1, CNA)CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H

Weakness (CWE)

CWE-367

Known exploited

Not in CISA's KEV catalog

EPSS (exploitation in the next 30 days)

Not loaded for this CVE

Assigned by

VulnCheck

NVD analysis

Deferred

Record last updated

Sep 30, 2026

First seen by InfoSec Signals

Oct 9, 2026

The CVE record on cve.org · NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.