Two vulnerabilities in Microsoft IIS FTP server

Published: 2009-08-31 | Updated: 2017-03-16

Risk	High
Patch available	YES
Number of vulnerabilities	2
CVE-ID	CVE-2009-2521 CVE-2009-3023
CWE-ID	CWE-20 CWE-121
Exploitation vector	Network
Public exploit	Vulnerability #1 is being exploited in the wild. Vulnerability #2 is being exploited in the wild.
Vulnerable software Subscribe	Microsoft IIS Server applications / Web servers
Vendor	Microsoft

Security Bulletin

This security bulletin contains information about 2 vulnerabilities.

1) Improper input validation

EUVDB-ID: #VU2794

Risk: High

CVSSv3.1: 6 [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]

CVE-ID: CVE-2009-2521

CWE-ID: CWE-20 - Improper input validation

Exploit availability: Yes

Description

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.

Mitigation

Install update from vendor's website:

Microsoft Internet Information Services 5.0 on
Microsoft Windows 2000 Service Pack 4:
https://www.microsoft.com/downloads/details.aspx?familyid=7fecd367-aaff-458b-91bc-8925c8e57528
Microsoft Internet Information Services 5.1 on
Windows XP Service Pack 2 and Windows XP Service Pack 3:
https://www.microsoft.com/downloads/details.aspx?familyid=2ae0bdd4-f8b2-420a-b1ac-d2cdaa87c828
Microsoft Internet Information Services 6.0 on
Windows XP Professional x64 Edition Service Pack 2:
https://www.microsoft.com/downloads/details.aspx?familyid=819dd2d1-cad5-4784-9baf-185d8a76df5d
Microsoft Internet Information Services 6.0 on
Windows Server 2003 Service Pack 2:
https://www.microsoft.com/downloads/details.aspx?familyid=48256ea3-b433-4e84-9019-22300069cfc1
Microsoft Internet Information Services 6.0 on
Windows Server 2003 x64 Edition Service Pack 2:
https://www.microsoft.com/downloads/details.aspx?familyid=61bded07-201e-4815-ac1e-468bf907e063
Microsoft Internet Information Services 6.0 on
Windows Server 2003 with SP2 for Itanium-based Systems:
https://www.microsoft.com/downloads/details.aspx?familyid=b99d4d9b-e0cc-4a8c-ad99-6a53958b37c8
Microsoft Internet Information Services 7.0 on
Windows Vista, Windows Vista Service Pack 1, and Windows Vista Service Pack 2:
https://www.microsoft.com/downloads/details.aspx?familyid=bb96eb1c-66a2-4276-9773-eea22179bcd4
Microsoft Internet Information Services 7.0 on
Windows Vista x64 Edition, Windows Vista x64 Edition Service Pack 1, and Windows Vista x64 Edition Service Pack 2:
https://www.microsoft.com/downloads/details.aspx?familyid=bce096c8-833b-45c8-99cd-1280f0744f2f
Microsoft Internet Information Services 7.0 on
Windows Server 2008 for 32-bit Systems and Windows Server 2008 for 32-bit Systems Service Pack 2:
https://www.microsoft.com/downloads/details.aspx?familyid=d9c5039f-d0cf-4d84-850f-f2f7701dcb79
Microsoft Internet Information Services 7.0 on
Windows Server 2008 for x64-based bit Systems and Windows Server 2008 for x64-based Systems Service Pack 2:
https://www.microsoft.com/downloads/details.aspx?familyid=db969ddc-708e-42b7-9956-6c27bf346bbb
Microsoft Internet Information Services 7.0 on
Windows Server 2008 for Itanium-based Systems and Windows Server 2008 for Itanium-based Systems Service Pack 2:
https://www.microsoft.com/downloads/details.aspx?familyid=a221451a-cb4e-4a43-a225-4b1e86e87525

Vulnerable software versions

Microsoft IIS: 5.0 - 7.0

External links

http://technet.microsoft.com/en-us/library/security/ms09-053.aspx

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote authenticated user via the Internet.

How the attacker can exploit this vulnerability?

The attacker would have to send a specially crafted request to the affected application in order to exploit this vulnerability.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability. However, a fully functional exploit for this vulnerability is available.

2) Stack-based buffer overflow

EUVDB-ID: #VU2795

Risk: High

CVSSv3.1: 9.2 [CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H/E:F/RL:O/RC:C]

CVE-ID: CVE-2009-3023

CWE-ID: CWE-121 - Stack-based buffer overflow

Exploit availability: Yes

Description

The vulnerability allows a remote authenticated attacker to execute arbitrary code on the target system.

The weakness exists due to stack-based buffer overflow in FTP server. A remote authenticated attacker can send a specially crafted FTP NLST command containing a wildcard that references a subdirectory, trigger memory corruption and execute arbitrary code on the system with privileges of the current user.

Successful exploitation of the vulnerability results in arbitrary code execution on the vulnerable system.

Note: the vulnerability was being actively exploited.

Mitigation

Vulnerable software versions

Microsoft IIS: 5.0 - 6.0

External links

http://technet.microsoft.com/en-us/library/security/ms09-053.aspx

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote authenticated user via the Internet.

How the attacker can exploit this vulnerability?

The attacker would have to send a specially crafted request to the affected application in order to exploit this vulnerability.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability. However, a fully functional exploit for this vulnerability is available.