Description
ProFTPD 1.3.7a contains a denial of service vulnerability that allows attackers to overwhelm the server by creating multiple simultaneous FTP connections. Attackers can repeatedly establish connections using threading to exhaust server connection limits and block legitimate user access.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| ProFTPD | ProFTPD | 1.3.7a | — |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 26.10 | proftpd-dfsg | No fix yet | — |
| Ubuntu 26.04 LTS | proftpd-dfsg | No fix yet | — |
| Ubuntu 25.10 | proftpd-dfsg | No fix yet | — |
| Ubuntu 24.04 LTS | proftpd-dfsg | No fix yet | — |
| Ubuntu 22.04 LTS | proftpd-dfsg | No fix yet | — |
Show 3 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 20.04 LTS | proftpd-dfsg | No fix yet | — |
| Ubuntu 18.04 LTS | proftpd-dfsg | No fix yet | — |
| Ubuntu 16.04 LTS | proftpd-dfsg | No fix yet | — |
Advisories 1
- WID-SEC-2026-0189 ProFTPD: Schwachstelle ermöglicht Denial of Service BSI CERT-Bund (WID) · Jan 21, 2026
References
- ExploitDB-49697 exploit
- ProFTPD Official Website product
- ProFTPD GitHub Repository issue-tracking
- VulnCheck Advisory: ProFTPD 1.3.7a - Remote Denial of Service third-party-advisory