CVE-2011-2523 Command injection in vsftpd

What is CVE-2011-2523?

CVE-2011-2523 is a critical command injection vulnerability in Debian Debian Linux, published on 27 Nov 2019. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

vsftpd 2.3.4 downloaded between 20110630 and 20110703 contains a backdoor which opens a shell on port 6200/tcp.

Weakness: CWE-78

Which versions are affected by CVE-2011-2523?

It affects 2 products.

Products include Debian Debian Linux, Vsftpd Project Vsftpd.

How do I fix CVE-2011-2523?

No fix has been published for CVE-2011-2523 yet. Limit exposure of the affected software until one is available.

Upgrade, and pass arguments to programs as a list instead of through a shell. More about Command injection.

Is CVE-2011-2523 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2011-2523 exists.

Public exploit code: 1 Metasploit module, 2 Exploit-DB entries, 1 Nuclei template and 70 proofs of concept on GitHub.

Other vulnerabilities in Debian Debian Linux

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• CVE-2025-49113 RoundCube Webmail Deserialization of Untrusted Data Exploited Critical 9.9
• CVE-2026-24061 GNU InetUtils Argument Injection Exploited Critical 9.8
• CVE-2025-39682 Linux Kernel Improper Check for Unusual or Exceptional Conditions Exploited Critical 9.8
• CVE-2024-9680 Mozilla Firefox Use-After-Free Exploited Critical 9.8

All Debian Debian Linux vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as GHSA-qf3g-hgw2-8r8h.