After identifying a significant overlap between IPs exploiting CVE-2024-40891 and those classified as Mirai, the team investigated a recent variant of Mirai and confirmed that the ability to exploit CVE-2024-40891 has been incorporated into some Mirai strains.

‍GreyNoise is observing active exploitation attempts targeting a zero-day critical command injection vulnerability in Zyxel CPE Series devices tracked as CVE-2024-40891. At this time, the vulnerability is not patched, nor has it been publicly disclosed. Attackers can leverage this vulnerability to execute arbitrary commands on affected devices, leading to complete system compromise, data exfiltration, or network infiltration. At publication, Censys is reporting over 1,500 vulnerable devices online.