Vulnerability identifier: #VU45231

Vulnerability risk: Medium

CVSSv3.1: 4.8 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L/E:P/RL:O/RC:C]

CVE-ID: CVE-2011-1137

CWE-ID: CWE-20

Exploitation vector: Network

Exploit availability: Yes

Vulnerable software:
ProFTPD
Server applications / File servers (FTP/HTTP)

Vendor: ProFTPD

Description

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

Integer overflow in the mod_sftp (aka SFTP) module in ProFTPD 1.3.3d and earlier allows remote attackers to cause a denial of service (memory consumption leading to OOM kill) via a malformed SSH message.

Mitigation
Install update from vendor's website.

Vulnerable software versions

ProFTPD: 1.2.0 - 1.3.3

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External links
http://bugs.proftpd.org/show_bug.cgi?id=3586
http://bugs.proftpd.org/show_bug.cgi?id=3587
http://lists.fedoraproject.org/pipermail/package-announce/2011-April/058344.html
http://lists.fedoraproject.org/pipermail/package-announce/2011-April/058356.html
http://proftp.cvs.sourceforge.net/viewvc/proftp/proftpd/contrib/mod_sftp/mod_sftp.c?r1=1.29.2.1&r2=1.29.2.2
http://proftp.cvs.sourceforge.net/viewvc/proftp/proftpd/contrib/mod_sftp/packet.c?r1=1.14.2.2&r2=1.14.2.3
http://proftp.cvs.sourceforge.net/viewvc/proftp/proftpd/contrib/mod_sftp/packet.h?r1=1.3&r2=1.3.2.1
http://secunia.com/advisories/43234
http://secunia.com/advisories/43635
http://secunia.com/advisories/43978
http://slackware.com/security/viewer.php?l=slackware-security&y=2011&m=slackware-security.485806
http://www.debian.org/security/2011/dsa-2185
http://www.exploit-db.com/exploits/16129/
http://www.securityfocus.com/bid/46183
http://www.vupen.com/english/advisories/2011/0617
http://www.vupen.com/english/advisories/2011/0857
http://bugzilla.redhat.com/show_bug.cgi?id=681718

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Q & A

Can this vulnerability be exploited remotely?

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

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability. However, proof of concept for this vulnerability is available.