Vulnerability identifier: #VU66691

Vulnerability risk: High

CVSSv3.1: 7.1 [CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2022-37452

CWE-ID: CWE-122

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Exim
Server applications / Mail servers

Vendor: Exim

Description

The vulnerability allows a remote attacker to execute arbitrary code on the target system.

The vulnerability exists due to a boundary error for the alias list within the host_name_lookup() function in host.c when the sender_host_name is set. A remote attacker can initiate a connection to the affected server, trigger a heap-based buffer overflow and execute arbitrary code on the target system.

Successful exploitation of this vulnerability may result in complete compromise of vulnerable system.

Mitigation
Install update from vendor's website.

Vulnerable software versions

Exim: 4.00 - 4.94.2

---

External links
http://www.exim.org/static/doc/security/
http://github.com/ivd38/exim_overflow
http://www.openwall.com/lists/oss-security/2022/08/06/8
http://github.com/Exim/exim/commit/d4bc023436e4cce7c23c5f8bb5199e178b4cc743
http://github.com/Exim/exim/wiki/EximSecurity
http://github.com/Exim/exim/compare/exim-4.94...exim-4.95

---

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.