Input validation error in Exim

1) Input validation error

EUVDB-ID: #VU41355

Risk: Medium

CVSSv3.1: 6.4 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L/E:U/RL:O/RC:C]

CVE-ID: CVE-2014-2957

CWE-ID: CWE-20 - Improper input validation

Exploit availability: No

Description

The vulnerability allows a remote non-authenticated attacker to read and manipulate data.

The dmarc_process function in dmarc.c in Exim before 4.82.1, when EXPERIMENTAL_DMARC is enabled, allows remote attackers to execute arbitrary code via the From header in an email, which is passed to the expand_string function.

Mitigation

Install update from vendor's website.

Vulnerable software versions

Exim: 4.00 - 4.80.1

External links

http://git.exim.org/exim.git/commitdiff/5b7a7c051c9ab9ee7c924a611f90ef2be03e0ad0
http://lists.exim.org/lurker/message/20140528.122536.a31d60a4.en.html

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.