CVE-2026-101088 (GCVE-0-2026-101088)

Vulnerability from cvelistv5 – Published: 2026-09-27 20:49 – Updated: 2026-09-30 22:13
VLAI
Title
Nezha before 2.3.1 Denial of Service via Concurrent Server Delete
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.
Severity
6 (Medium)
CVSS:4.0/AV:N/AC:H/AT:P/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
5.3 (Medium)
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-30 22:13 UTC
CWE
  • CWE-367 - Time-of-check Time-of-use (TOCTOU) Race Condition
Assigner
VulnCheck CNA under the mitre root
CNA scorecard B 84/100 over 7132 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
nezhahq nezha Affected: 2.2.11 , < 2.3.1 (semver)
Unaffected: 2.3.1 (semver)
guessed Create a notification for this product.
Date Public
2026-08-01 00:00
Credits
arpitjain099
Show details on NVD website
To clipboard 

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