Amazon Linux AMI update for exim

1) Release of invalid pointer or reference

EUVDB-ID: #VU66692

Risk: Medium

CVSSv4.0: 6.6 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2022-37451

CWE-ID: CWE-763 - Release of invalid pointer or reference

Exploit availability: No

Description

The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.

The vulnerability exists due to an invalid free in pam_converse() function in auths/call_pam.c. A remote attacker can initiate the connection to the affected mail server and perform a denial of service (DoS) attack.

Mitigation

Update the affected packages:

i686:
    exim-4.92-1.37.amzn1.i686
    exim-pgsql-4.92-1.37.amzn1.i686
    exim-mysql-4.92-1.37.amzn1.i686
    exim-debuginfo-4.92-1.37.amzn1.i686
    exim-greylist-4.92-1.37.amzn1.i686
    exim-mon-4.92-1.37.amzn1.i686

src:
    exim-4.92-1.37.amzn1.src

x86_64:
    exim-greylist-4.92-1.37.amzn1.x86_64
    exim-mon-4.92-1.37.amzn1.x86_64
    exim-mysql-4.92-1.37.amzn1.x86_64
    exim-4.92-1.37.amzn1.x86_64
    exim-pgsql-4.92-1.37.amzn1.x86_64
    exim-debuginfo-4.92-1.37.amzn1.x86_64

Vulnerable software versions

Amazon Linux AMI: All versions

exim: All versions

CPE2.3

• cpe:2.3:o:amazon_web_services:amazon_linux_ami:*:*:*:*:*:*:*:*
• cpe:2.3:a:amazon_web_services:exim:*:*:*:*:*:amazon_linux_ami:*:*

External links

https://alas.aws.amazon.com/ALAS-2023-1753.html

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.