CVE-2011-2523

Name: CVE-2011-2523
Creator: NVD / NIST
Published: 2019-11-27T21:15:12.387+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

CRITICALCVSS 9.8/10EPSS 96.18%

Last modified Jun 16, 2026

CVE-2011-2523 is a critical-severity vulnerability rated 9.8/10 on the CVSS scale. vsftpd 2.3.4 downloaded between 20110630 and 20110703 contains a backdoor which opens a shell on port 6200/tcp.. EPSS estimates a 96.18% chance of exploitation in the next 30 days.

Description

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

Metrics

CVSS 3.1

9.8/10

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

EPSS Probability

96.18%

99.9th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-78

Affected Software

Vendor	Product	Versions
Vsftpd Project	Vsftpd	2.3.4
Debian	Debian Linux	8.0
Debian	Debian Linux	9.0
Debian	Debian Linux	10.0

References

http://packetstormsecurity.com/files/162145/vsftpd-2.3.4-Backdoor-Command-Execution.html
https://access.redhat.com/security/cve/cve-2011-2523Third Party Advisory
https://packetstormsecurity.com/files/102745/VSFTPD-2.3.4-Backdoor-Command-Execution.htmlExploit, Third Party Advisory, VDB Entry
https://security-tracker.debian.org/tracker/CVE-2011-2523Third Party Advisory
https://vigilance.fr/vulnerability/vsftpd-backdoor-in-version-2-3-4-10805Third Party Advisory
https://www.openwall.com/lists/oss-security/2011/07/11/5Mailing List, Third Party Advisory
http://packetstormsecurity.com/files/162145/vsftpd-2.3.4-Backdoor-Command-Execution.html
https://access.redhat.com/security/cve/cve-2011-2523Third Party Advisory
https://packetstormsecurity.com/files/102745/VSFTPD-2.3.4-Backdoor-Command-Execution.htmlExploit, Third Party Advisory, VDB Entry
https://security-tracker.debian.org/tracker/CVE-2011-2523Third Party Advisory
https://vigilance.fr/vulnerability/vsftpd-backdoor-in-version-2-3-4-10805Third Party Advisory
https://www.openwall.com/lists/oss-security/2011/07/11/5Mailing List, Third Party Advisory

Timeline

Published: Nov 27, 2019
Last Modified: Jun 16, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2011-2523?

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

How severe is CVE-2011-2523?

CVE-2011-2523 has a CVSS score of 9.8/10 (CRITICAL severity). The EPSS model estimates a 96.18% probability of exploitation in the next 30 days.

How do I fix CVE-2011-2523?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2011-2523?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST