Security restrictions bypass in msmtp

1) Security restrictions bypass

EUVDB-ID: #VU17765

Risk: Low

CVSSv3.1: 5.5 [CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L/E:U/RL:O/RC:C]

CVE-ID: CVE-2019-8337

CWE-ID: CWE-264 - Permissions, Privileges, and Access Controls

Exploit availability: No

Description

The vulnerability allows a remote authenticated attacker to bypass security restrictions on the system.

The vulnerability exists due to improper certificate verification when the affected software uses the new system default value for the  tls_trust_file command in its default configuration file. A remote attacker can send an email to an SMTP server and bypass certificate verification and conduct further attacks. 

Mitigation

Update to version 1.8.3.

Vulnerable software versions

msmtp: 1.8.2

External links

http://marlam.de/msmtp/news/

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote authenticated user 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.