Privilege escalation in Dovecot

1) Stack-based buffer overflow

EUVDB-ID: #VU18089

Risk: Low

CVSSv3.1: 7.7 [CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2019-7524

CWE-ID: CWE-121 - Stack-based buffer overflow

Exploit availability: No

Description

The vulnerability allows a local user to execute arbitrary code on the target system.

The vulnerability exists due to a boundary error when reading FTS or POP3-UIDL header from dovecot index. A local user can modify Dovecot index, trigger stack-based buffer overflow and execute arbitrary code on the target system with privileges of the Dovecot process.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

Dovecot: 2.0.14 - 2.3.5

External links

http://www.dovecot.org/list/dovecot-news/2019-March/000403.html

Q & A

Can this vulnerability be exploited remotely?

No. This vulnerability can be exploited locally. The attacker should have authentication credentials and successfully authenticate on the system.

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.

The attacker would have to login to the system and perform certain actions in order to exploit this vulnerability.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.