Input validation error in ProFTPD

1) Input validation error

EUVDB-ID: #VU42524

Risk: Medium

CVSSv3.1: 4.6 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L/E:U/RL:O/RC:C]

CVE-ID: CVE-2013-4359

CWE-ID: CWE-20 - Improper input validation

Exploit availability: No

Description

The vulnerability allows a remote non-authenticated attacker to perform service disruption.

Integer overflow in kbdint.c in mod_sftp in ProFTPD 1.3.4d and 1.3.5r3 allows remote attackers to cause a denial of service (memory consumption) via a large response count value in an authentication request, which triggers a large memory allocation.

Mitigation

Install update from vendor's website.

Vulnerable software versions

ProFTPD: 1.3.4 - 1.3.5

External links

http://bugs.proftpd.org/show_bug.cgi?id=3973
http://kingcope.wordpress.com/2013/09/11/proftpd-mod_sftpmod_sftp_pam-invalid-pool-allocation-in-kbdint-authentication/
http://lists.opensuse.org/opensuse-updates/2013-10/msg00032.html
http://lists.opensuse.org/opensuse-updates/2015-06/msg00020.html
http://www.debian.org/security/2013/dsa-2767
http://www.openwall.com/lists/oss-security/2013/09/17/6

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker 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.