Nezha Monitoring: Whole-instance DoS in Nezha dashboard: a member can crash the process for every tenant

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS

6.5 · CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

EPSS

• CVE-2026-100394: 0.50% estimated exploitation activity in the next 30 days; percentile 42.73 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

Summary A single low-privilege RoleMember can take the entire Nezha dashboard offline, and with it every tenant's web UI, REST API, and agent connections, by racing two ordinary operations on their own service. The crash is a nil pointer dereference in the service-monitor worker at service/singleton/servicesentinel.go:601. The worker checks a service exists under one lock and later writes to two pointer-valued status maps under a different lock; a concurrent delete removes the entries in the gap. Because the gRPC server has no recovery interceptor, the worker-goroutine panic kills the whole process. Availability only: nothing is read or modified. Affected versions Confirmed in v2.2.7 through v2.2.10. service/singleton/servicesentinel.go has the same vulnerable implementation in all four releases. The issue is fixed in v2.2.11 and later; users should upgrade to the latest release, v2.3.0. The bug The worker validates an incoming report and later writes it to two status maps, but the…

Published by the source

15 Oct 2026, 20:15 UTC

Last modified by the source

19 Oct 2026, 21:31 UTC

Source last checked

26 Oct 2026, 15:32 UTC

1. Revision 3 · amended · 26 Oct 2026

   Amended from ghsa record GHSA-qjpp-gffx-2wm9

2. Revision 2 · amended · 24 Oct 2026

   Amended from osv record GO-2026-6794

3. Revision 1 · created · 24 Oct 2026

   Published from osv record GHSA-qjpp-gffx-2wm9

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# Patch Next advisory brief: CVE-2026-100394

Advisory: Nezha Monitoring: Whole-instance DoS in Nezha dashboard: a member can crash the process for every tenant
IDs: CVE-2026-100394, GHSA-qjpp-gffx-2wm9
Record: https://patchnext.com/advisories/cve-2026-100394 (revision 3, source checked 26 Oct 2026, 15:32 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: Medium (CVSS 6.5)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: github.com/nezhahq/nezha 0.0.0-20260721131105-c893aa57867d. A vendor fix does not mean a deployment is fixed.

## Affected components
- Go github.com/nezhahq/nezha: affected >= 0.0.0-20260628010923-fd31e5f1b0f8, < 0.0.0-20260721131105-c893aa57867d; fixed in 0.0.0-20260721131105-c893aa57867d

## Suggested inspection (read-only)
- Go github.com/nezhahq/nezha: check the installed version with your package manager.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on github.com/nezhahq/nezha.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://osv.dev/vulnerability/GO-2026-6794 (OSV record GO-2026-6794 lists affected ranges: Go github.com/nezhahq/nezha >=0.0.0-20260628010923-fd31e5f1b0f8 <0.0.0-20260721131105-c893aa57867d (fixed))
- Verified: https://osv.dev/vulnerability/GHSA-qjpp-gffx-2wm9 (OSV record GHSA-qjpp-gffx-2wm9 lists affected ranges: Go github.com/nezhahq/nezha >=0.0.0-20260628010923-fd31e5f1b0f8 <0.0.0-20260721131105-c893aa57867d (fixed))
- Verified: https://github.com/advisories/GHSA-qjpp-gffx-2wm9 (GitHub-reviewed advisory GHSA-qjpp-gffx-2wm9 lists affected ranges: Go github.com/nezhahq/nezha >=0.0.0-20260628010923-fd31e5f1b0f8 <0.0.0-20260721131105-c893aa57867d)

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