---
title: "NET-DB-006 Memcached UDP or Broad Listen Address"
canonical: https://openvapt.com/checks/NET-DB-006.html
html: https://openvapt.com/checks/NET-DB-006.html
site: OpenVAPT, https://openvapt.com/
license: OpenVAPT Source-Available Licence 1.3, https://openvapt.com/legal/licence-text.html
modified: 2026-10-14
version: 0.1.0-alpha.6
---

# NET-DB-006 Memcached UDP or Broad Listen Address

Memcached enables UDP or listens on a non-loopback address.

- Domain: Network
- Severity: High
- Control category: Data Services
- Fix effort: low
- CVSS v3.1 vector: `CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H`
- CIS Controls v8: 4.1
- NIST CSF 2.0: PR.PS-01
- CWE: CWE-406, CWE-1188
- OWASP Top 10 2021: A05:2021
- NIST SP 800-53 Rev. 5: SC-5, CM-6, SC-7
- Benchmark topic: Secure data service configuration (topic only, no benchmark text)

## Why It Matters

Unauthenticated Memcached exposure can disclose cached data and UDP mode has been abused for amplification attacks.

## How It Detects

Parses memcached.conf (one option per line) and /etc/sysconfig/memcached (OPTIONS and UDP_PORT) for -U or UDP_PORT and -l. A UDP port other than 0 fails; a listen address fails unless every address is loopback (127.0.0.1, ::1 or localhost); no -l at all means every interface and fails. The actual values are the evidence.

## How to Fix

Set UDP_PORT=0 or -U 0 and bind with -l 127.0.0.1. Use a firewall for any explicitly required clients.

## How to Verify

```
Confirm ss -ltnup shows Memcached only on loopback and no UDP port 11211.
```

## Learn the Theory

- [P3 Network Exposure and Firewalls](https://openvapt.com/academy/p3.md)
- [P8 Data Services: Databases, File Shares, DNS and Mail](https://openvapt.com/academy/p8.md)

## References

- [memcached Configuration](https://docs.memcached.org/serverguide/configuring/)

## Source Code

https://github.com/OpenVAPT/openvapt/blob/574f7f3333c44b75a3c649e2d93a76d507f75adf/internal/checks/network/data_services.go

Run it: `openvapt scan --only NET-DB-006`. Read it offline: `openvapt explain NET-DB-006`.

---

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