Remote code execution in libspf2

1) Heap-based buffer overflow

EUVDB-ID: #VU66695

Risk: High

CVSSv3.1: 7.4 [CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H/E:U/RL:U/RC:C]

CVE-ID: CVE-2021-33913

CWE-ID: CWE-122 - Heap-based Buffer Overflow

Exploit availability: No

Description

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

The vulnerability exists due to a boundary error within the spf_expand.c when parsing SPF DNS records. A remote attacker can send an email 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

Cybersecurity Help is currently unaware of any official solution to address this vulnerability..

Vulnerable software versions

libspf2: 1.0.2 - 1.2.10

External links

http://github.com/shevek/libspf2/tree/8131fe140704eaae695e76b5cd09e39bd1dd220b
http://nathanielbennett.com/blog/libspf2-cve-jan-2022-disclosure
http://lists.debian.org/debian-lts-announce/2022/01/msg00015.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.