Zero-day vulnerability in Microsoft IIS

Improper input validation

The issue has been introduced in 02/17/2000. The weakness was disclosed on 09/04/2009 by Kingcope.

Vulnerability details

Advisory: SB2009083101 - Two vulnerabilities in Microsoft IIS FTP server

Vulnerable component: Microsoft IIS

CVE-ID: CVE-2009-2521

CVSSv3 score: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H/E:F/RL:O/RC:C

CWE-ID: CWE-20 - Improper input validation


The vulnerability allows a remote authenticated attacker to cause DoS conditions on the target system.

The weakness exists due to an error when processing recursive directory listing commands by the FTP Service. By sending a specially crafted LIST command containing wildcard characters, a remote attacker can trigger the FTP service to crash.

Successful exploitation of the vulnerability results in denial of service on the vulnerable system.

Note: the vulnerability was being actively exploited.

Public Exploits: