Multiple vulnerabilities in Fail2ban

Published: 2014-02-01 | Updated: 2020-08-10

Risk	Medium
Patch available	YES
Number of vulnerabilities	2
CVE-ID	CVE-2013-7176 CVE-2013-7177
CWE-ID	CWE-20
Exploitation vector	Network
Public exploit	N/A
Vulnerable software Subscribe	Fail2ban Server applications / IDS/IPS systems, Firewalls and proxy servers
Vendor	Fail2ban

Security Bulletin

This security bulletin contains information about 2 vulnerabilities.

1) Input validation error

EUVDB-ID: #VU42086

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-2013-7176

CWE-ID: CWE-20 - Improper input validation

Exploit availability: No

Description

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

config/filter.d/postfix.conf in the postfix filter in Fail2ban before 0.8.11 allows remote attackers to trigger the blocking of an arbitrary IP address via a crafted e-mail address that matches an improperly designed regular expression.

Mitigation

Install update from vendor's website.

Vulnerable software versions

Fail2ban: 0.1.0 - 0.8.9

External links

http://lists.opensuse.org/opensuse-updates/2014-03/msg00021.html
http://www.debian.org/security/2014/dsa-2979
http://www.kb.cert.org/vuls/id/686662
http://github.com/fail2ban/fail2ban/commit/eb2f0c927257120dfc32d2450fd63f1962f38821

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.

2) Input validation error

EUVDB-ID: #VU42087