#VU45231 Input validation error in ProFTPD - CVE-2011-1137

Vulnerability identifier: #VU45231

Vulnerability risk: Medium

CVSSv4.0: 5.5 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:P/U:Green]

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