CVE-2010-20121

Name: CVE-2010-20121
Creator: NVD / NIST
Published: 2025-08-21T20:15:31.61+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

CRITICALCVSS 9.3/10EPSS 3.03%

Last modified Jun 16, 2026

CVE-2010-20121 is a critical-severity vulnerability rated 9.3/10 on the CVSS scale. EasyFTP Server versions up to 1.7.0.11 contain a stack-based buffer overflow vulnerability in the FTP command parser. When processing the CWD (Change Working Directory) command, the server fails to properly validate the length of the input string, allowing attackers to overwrite memory on the stack. EPSS estimates a 3.03% chance of exploitation in the next 30 days.

Description

EasyFTP Server versions up to 1.7.0.11 contain a stack-based buffer overflow vulnerability in the FTP command parser. When processing the CWD (Change Working Directory) command, the server fails to properly validate the length of the input string, allowing attackers to overwrite memory on the stack. This flaw enables remote code execution without authentication, as EasyFTP allows anonymous access by default. The vulnerability was resolved in version 1.7.0.12, after which the product was renamed “UplusFtp.”

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

CVSS 4.0

9.3/10

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

EPSS Probability

3.03%

85.8th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-121

Affected Software

Vendor	Product	Versions
Easyftp Server Project	Easyftp Server	< 1.7.0.12

References

https://paulmakowski.wordpress.com/2010/02/28/increasing-payload-size-w-return-address-overwrite/Exploit, Third Party Advisory
https://raw.githubusercontent.com/rapid7/metasploit-framework/master/modules/exploits/windows/ftp/easyftp_cwd_fixret.rbExploit
https://seclists.org/bugtraq/2010/Feb/202Exploit, Mailing List, Third Party Advisory
https://www.exploit-db.com/exploits/11668Exploit, VDB Entry
https://www.exploit-db.com/exploits/12312Exploit, VDB Entry
https://www.exploit-db.com/exploits/14402Exploit, VDB Entry
https://www.exploit-db.com/exploits/16737Exploit, VDB Entry
https://www.vulncheck.com/advisories/easyftp-server-cwd-command-stack-buffer-overflowThird Party Advisory
https://raw.githubusercontent.com/rapid7/metasploit-framework/master/modules/exploits/windows/ftp/easyftp_cwd_fixret.rbExploit
https://seclists.org/bugtraq/2010/Feb/202Exploit, Mailing List, Third Party Advisory
https://www.exploit-db.com/exploits/11668Exploit, VDB Entry
https://www.exploit-db.com/exploits/12312Exploit, VDB Entry
https://www.exploit-db.com/exploits/14402Exploit, VDB Entry
https://www.exploit-db.com/exploits/16737Exploit, VDB Entry

Timeline

Published: Aug 21, 2025
Last Modified: Jun 16, 2026
Status: Analyzed

Frequently Asked Questions

What is CVE-2010-20121?

How severe is CVE-2010-20121?

CVE-2010-20121 has a CVSS score of 9.3/10 (CRITICAL severity). The EPSS model estimates a 3.03% probability of exploitation in the next 30 days.

How do I fix CVE-2010-20121?

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-2010-20121?

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

Scan your code now

Source: NVD / NIST