Remote code executioin in OpenSLP service in VMware ESXi

1) Heap-based buffer overflow

EUVDB-ID: #VU50900

Risk: High

CVSSv4.0: 8.7 [CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:A/U:Amber]

CVE-ID: CVE-2021-21974

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

Exploit availability: Yes

Description

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

The vulnerability exists due to a boundary error when processing packets within the OpenSLP service. A remote non-authenticated attacker on the local network can send specially crafted SLP messages to port 427/tcp, 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.

Note, the vulnerability is being actively exploited in the wild.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

VMware ESXi: ESXi_7.0.0-1.20.16321839 - 7.0

CPE2.3

• cpe:2.3:o:vmware:vmware_esxi:ESXi_7.0.0-1.20.16321839:*:*:*:*:*:*:*
• cpe:2.3:o:vmware:vmware_esxi:ESXi_7.0.1-0.0.16850804:*:*:*:*:*:*:*
• cpe:2.3:o:vmware:vmware_esxi:ESXi70U1b-17168206:*:*:*:*:*:*:*

External links

https://www.vmware.com/security/advisories/VMSA-2021-0002.html
https://kb.vmware.com/s/article/76372
https://www.zerodayinitiative.com/advisories/ZDI-21-250/

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the local network (LAN).

Is there known malware, which exploits this vulnerability?

Yes. This vulnerability is being exploited in the wild.