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TI-2026-22094 Aliases CVE-2026-27734GHSA-phwh-4f42-gwf3

Beszel Vulnerable to Docker API Path Traversal via Unsanitized Container ID

Priority LOW 30CWE-22Published · Updated

Key facts

Attack vector
Network
Privileges required
Low
User interaction
None
Attack complexity
Low
Impact type
Information disclosure
Confidentiality · integrity · availability
High · None · None
Fix status
Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA and GitHub. Impact type from CWE-22 and the CVSS impact.

Summary

Beszel is a server monitoring platform. Prior to version 0.18.2, the hub's authenticated API endpoints GET /api/beszel/containers/logs and GET /api/beszel/containers/info pass the user-supplied "container" query parameter to the agent without validation. The agent constructs Docker Engine API URLs using fmt.Sprintf with the raw value instead of url.PathEscape(). Since Go's http.Client does not sanitize `../` sequences from URL paths sent over unix sockets, an authenticated user (including readonly role) can traverse to arbitrary Docker API endpoints on agent hosts, exposing sensitive infrastructure details. Version 0.18.4 fixes the issue.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00545 45th percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by NVD
Fix Fixed beszel (henrygd): 0.18.4github.com/henrygd/beszel (Go): 0.18.4

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
henrygdbeszelbefore 0.18.40.18.4Patch availableCNA
—github.com/henrygd/beszel (Go)before 0.18.40.18.4Patch availableGHSA-phwh-4f42-gwf3
  • beszel Vendorhenrygd Affected before 0.18.4 Fixed in 0.18.4 Patch available CNA
  • github.com/henrygd/beszel (Go) Vendor— Affected before 0.18.4 Fixed in 0.18.4 Patch available GHSA-phwh-4f42-gwf3

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:beszel:beszel:*:*:*:*:*:*:*:*before 0.18.2VulnerableBeszel
  • cpe:2.3:a:beszel:beszel:*:*:*:*:*:*:*:* Versions before 0.18.2 Vulnerable ·Beszel

Remediation

  • Fix · CNA beszel (henrygd) Fixed in 0.18.4
  • Fix · GHSA-phwh-4f42-gwf3 github.com/henrygd/beszel (Go) Fixed in 0.18.4 Advisory →

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-27734
  2. 2026-10-03 Alias added: GHSA-phwh-4f42-gwf3

References

Exploit 1

Advisory 1

Other 3

  • TI-2026-63405 Beszel before 0.19.0 Insecure Direct Object Reference via user-alerts CVSS 4.0LOW 2.3

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences