Description
vsftpd through 3.0.5 contains an access control bypass vulnerability that allows authenticated FTP users to execute denied commands by issuing RFC 775 X-prefixed aliases. The cmds_denied check in process_post_login() compares literal tokens, so attackers can send XRMD, XMKD, XCWD, XPWD, or XCUP to perform blocked operations like deleting directories.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| vsftpd | vsftpd | ≤ 3.0.5 | — |
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.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | vsftpd | No fix yet | — |
| Debian 13 | vsftpd | No fix yet | — |
| Debian 12 | vsftpd | No fix yet | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 26.10 | vsftpd | No fix yet | — |
| Ubuntu 26.04 LTS | vsftpd | No fix yet | — |
| Ubuntu 24.04 LTS | vsftpd | No fix yet | — |
| Ubuntu 22.04 LTS | vsftpd | No fix yet | — |
| Ubuntu 20.04 LTS | vsftpd | No fix yet | — |
Show 3 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 18.04 LTS | vsftpd | No fix yet | — |
| Ubuntu 16.04 LTS | vsftpd | No fix yet | — |
| Ubuntu 14.04 LTS | vsftpd | No fix yet | — |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 15 SP5 | vsftpd | 3.0.5-150400.3.19.1 | SUSE-SU-2026:5222-1 |
| SLES 15 SP4 | vsftpd | 3.0.5-150400.3.19.1 | SUSE-SU-2026:5222-1 |
Show 4 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES for SAP 15 SP5 | vsftpd | 3.0.5-150400.3.19.1 | SUSE-SU-2026:5222-1 |
| SLES for SAP 15 SP4 | vsftpd | 3.0.5-150400.3.19.1 | SUSE-SU-2026:5222-1 |
| SLE HPC 15 SP5 | vsftpd | 3.0.5-150400.3.19.1 | SUSE-SU-2026:5222-1 |
| SLE HPC 15 SP4 | vsftpd | 3.0.5-150400.3.19.1 | SUSE-SU-2026:5222-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | vsftpd | 3.0.5-21.1 | openSUSE-SU-2026:12522-1 |
Azure Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Azure Linux 3 | vsftpd | No fix yet | — |
Advisories 2
- SUSE-SU-2026:5222-1 Security update for vsftpd SUSE / openSUSE Security Updates · Nov 13, 2026
- openSUSE-SU-2026:12522-1 vsftpd-3.0.5-21.1 on GA media SUSE / openSUSE Security Updates · Nov 11, 2026
References
- https://abraxaslabs.tech/research/vsftpd-cmds-denied-alias third-party-advisory
- https://security.appspot.com/vsftpd.html product
- VulnCheck Advisory: vsftpd through 3.0.5 cmds_denied Bypass via RFC 775 Command Aliases third-party-advisory