Nezha Monitoring: Authenticated users can claim the dashboard Host through NAT and preempt all dashboard routing

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-2026-53520: 0.34% estimated exploitation activity in the next 30 days; percentile 27.43 (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 An authenticated non-admin user who owns any server can create or update a NAT profile whose domain is equal to the dashboard's own HTTP Host (for example, dashboard.example:8008). The dashboard's top-level HTTP/gRPC multiplexer checks NATShared.GetNATConfigByDomain(r.Host) before dispatching requests to the dashboard API, frontend, or gRPC handler, so a member-controlled NAT profile for the dashboard Host takes precedence over the real dashboard. A disabled claimed NAT profile blocks matching dashboard requests before they reach the dashboard handler. An enabled claimed NAT profile routes matching requests into ServeNAT, which sends a NAT task to the member's selected agent and wraps the original HTTP request into the NAT IO stream. This allows a low-privileged dashboard user to take over routing for a global host name that should be reserved for the dashboard operator. Tested locally against commit 8b5e382fe217107c7b777ea9c6b4bc3d2e156202 of github.com/nezhahq/nezha.…

Published by the source

26 Jun 2026, 23:00 UTC

Last modified by the source

26 Jun 2026, 23:00 UTC

Source last checked

26 Oct 2026, 15:24 UTC

1. Revision 1 · created · 26 Oct 2026

   Published from ghsa record GHSA-x6fg-52vr-hj4w

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# Patch Next advisory brief: CVE-2026-53520

Advisory: Nezha Monitoring: Authenticated users can claim the dashboard Host through NAT and preempt all dashboard routing
IDs: CVE-2026-53520, GHSA-x6fg-52vr-hj4w
Record: https://patchnext.com/advisories/cve-2026-53520 (revision 1, source checked 26 Oct 2026, 15:24 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 2.1.0. A vendor fix does not mean a deployment is fixed.

## Affected components
- Go github.com/nezhahq/nezha: affected >= 2.0.14, < 2.1.0; fixed in 2.1.0

## 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://github.com/advisories/GHSA-x6fg-52vr-hj4w (GitHub-reviewed advisory GHSA-x6fg-52vr-hj4w lists affected ranges: Go github.com/nezhahq/nezha >=2.0.14 <2.1.0)

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