Beszel has an IDOR in hub API endpoints that read system ID from URL parameter

Exploitation

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

CVSS

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

EPSS

• CVE-2026-40077: 0.22% estimated exploitation activity in the next 30 days; percentile 12.52 (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 Some API endpoints in the Beszel hub accept a user-supplied system ID and proceed without further checks that the user should have access to that system. As a result, any authenticated user can access these routes for any system if they know the system's ID. System IDs are random 15 character alphanumeric strings, and are not exposed to all users. However, it is theoretically possible for an authenticated user to enumerate a valid system ID via web API. To use the containers endpoints, the user would also need to enumerate a container ID, which is 12 digit hexadecimal string. Affected Component - File: internal/hub/api.go, lines 283–361 - Endpoints: - GET /api/beszel/containers/logs?system=SYSTEMID&container=CONTAINERID - GET /api/beszel/containers/info?system=SYSTEMID&container=CONTAINERID - GET /api/beszel/systemd/info?system=SYSTEMID&service=SERVICENAME - POST /api/beszel/smart/refresh?system=SYSTEMID - Commit: c7261b56f1bfb9ae57ef0856a0052cabb2fd3b84 Vulnerable Code The…

Published by the source

10 Apr 2026, 17:32 UTC

Last modified by the source

10 Apr 2026, 17:32 UTC

Source last checked

26 Oct 2026, 15:19 UTC

1. Revision 1 · created · 26 Oct 2026

   Published from ghsa record GHSA-5f5r-95pg-xrpm

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# Patch Next advisory brief: CVE-2026-40077

Advisory: Beszel has an IDOR in hub API endpoints that read system ID from URL parameter
IDs: CVE-2026-40077, GHSA-5f5r-95pg-xrpm
Record: https://patchnext.com/advisories/cve-2026-40077 (revision 1, source checked 26 Oct 2026, 15:19 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: Low (CVSS 3.5)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: github.com/henrygd/beszel 0.18.7. A vendor fix does not mean a deployment is fixed.

## Affected components
- Go github.com/henrygd/beszel: affected <= 0.18.6; fixed in 0.18.7

## Suggested inspection (read-only)
- Go github.com/henrygd/beszel: 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/henrygd/beszel.
- 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-5f5r-95pg-xrpm (GitHub-reviewed advisory GHSA-5f5r-95pg-xrpm lists affected ranges: Go github.com/henrygd/beszel >=0 <=0.18.6)

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