#VU22564 Infinite loop in ProFTPD - CVE-2019-18217

Vulnerability identifier: #VU22564

Vulnerability risk: Medium

CVSSv4.0: 2.7 [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:U/U:Green]

CVE-ID: CVE-2019-18217

CWE-ID: CWE-835

Exploitation vector: Network

Exploit availability: No

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

Vendor: ProFTPD

Description

The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.

The vulnerability exists due to infinite loop in main.c in a child process when handling overly long commands. A remote non-authenticated attacker can perform a denial of service attack by sending an overly log command to the affected FTP server.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

ProFTPD: 1.3.0a - 1.3.6

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External links
https://github.com/proftpd/proftpd/blob/1.3.6/NEWS
https://github.com/proftpd/proftpd/blob/1.3.6/RELEASE_NOTES
https://github.com/proftpd/proftpd/blob/master/NEWS
https://github.com/proftpd/proftpd/blob/master/RELEASE_NOTES
https://github.com/proftpd/proftpd/issues/846

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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.