CVE-2026-100394 Nezha Monitoring: Whole-instance DoS in Nezha dashboard: a member can crash the process for every tenant
A race condition allows a member to crash the entire Nezha Monitoring dashboard process, denying service to all tenants.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-100394?
CVE-2026-100394 is a medium-severity vulnerability in nezhahq nezha, published on 14 Oct 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
Nezha Monitoring is a self-hostable, lightweight, servers and websites monitoring and O&M tool. From 2.2.7 until 2.2.11, ServiceSentinel.worker in service/singleton/servicesentinel.go checked an owned service under servicesLock and later dereferenced pointer-valued serviceStatusToday and serviceCurrentStatusData entries under serviceResponseDataStoreLock without revalidating that ServiceSentinel.Delete had not removed them. A RoleMember could concurrently report TCP or ICMP results through the member's own agent and delete the same owned service, causing a nil pointer dereference. Because the gRPC server had no recovery interceptor, the worker panic terminated the whole dashboard process and disrupted every tenant's web interface, REST API, and agent connections. The issue affects availability only and does not disclose or modify data. This issue is fixed in versions 2.2.11 and 2.3.0.
Which versions are affected by CVE-2026-100394?
3 open source packages ship an affected version, including github.com/nezhahq/nezha.
| Package | Affected | Fixed in |
|---|---|---|
github.com/nezhahq/nezha Go | From 0.0.0-20260628010923-fd31e5f1b0f8 | 0.0.0-20260721131105-c893aa57867d |
github.com/nezhahq/nezha Go | From 0.0.0-20260628010923-fd31e5f1b0f8 | 0.0.0-20260721131105-c893aa57867d |
github.com/nezhahq/nezha Go | From 0.0.0-20260628010923-fd31e5f1b0f8 | 0.0.0-20260721131105-c893aa57867d |
How do I fix CVE-2026-100394?
Upgrade github.com/nezhahq/nezha to 0.0.0-20260721131105-c893aa57867d or later.
Is CVE-2026-100394 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-100394 exists.
Sources
Also known as GHSA-qjpp-gffx-2wm9, GO-2026-6794.