Cisco Talos identified a previously unknown state-sponsored actor behind ArcaneDoor, a sophisticated cyber espionage campaign targeting the perimeter network devices of several vendors. This actor is now tracked as UAT4356 by Talos and STORM-1849 by the Microsoft Threat Intelligence Center.
The initial attack vector is still unknown, but the attacker exploited two previously unknown vulnerabilities. An official fix is now available for both.
| CVE Number | CVSS | EPSS | 
| CVE-2024-20353 | 8.6 (High) | 0.23% (Low) | 
| CVE-2024-20359 | 6.0 (Medium) | 0.14% (Low) | 
The threat actor deployed two backdoors as components of this campaign, dubbed “Line Dancer” and “Line Runner.” They were used to conduct malicious actions on-target, which included configuration modification, reconnaissance, network traffic capture/exfiltration and potentially lateral movement. Line Dancer is a memory-resident shellcode interpreter that enables adversaries to upload and execute arbitrary shellcode payloads. Line Runner was used to maintain persistence on the compromised device and used to retrieve information staged through the use of Line Dancer.

Cisco Talos listed the infrastructure controlled by UAT4356 in its blog post. The following IP addresses were used by the actor. Some of these IPs are part of publicly known anonymization infrastructure that is not directly controlled by the attackers.
192.36.57[.]181 
185.167.60[.]85 
185.227.111[.]17 
176.31.18[.]153 
172.105.90[.]154 
185.244.210[.]120 
45.86.163[.]224 
172.105.94[.]93 
213.156.138[.]77 
89.44.198[.]189 
45.77.52[.]253 
103.114.200[.]230 
212.193.2[.]48 
51.15.145[.]37 
89.44.198[.]196 
131.196.252[.]148 
213.156.138[.]78 
121.227.168[.]69 
213.156.138[.]68 
194.4.49[.]6 
185.244.210[.]65 
216.238.75[.]155 
5.183.95[.]95 
45.63.119[.]131 
45.76.118[.]87 
45.77.54[.]14 
45.86.163[.]244 
45.128.134[.]189    
89.44.198[.]16 
96.44.159[.]46 
103.20.222[.]218 
103.27.132[.]69 
103.51.140[.]101 
103.119.3[.]230 
103.125.218[.]198 
104.156.232[.]22 
107.148.19[.]88 
107.172.16[.]208 
107.173.140[.]111 
121.37.174[.]139 
139.162.135[.]12 
149.28.166[.]244 
152.70.83[.]47 
154.22.235[.]13 
154.22.235[.]17 
154.39.142[.]47  
172.233.245[.]241 
185.123.101[.]250 
192.210.137[.]35  
194.32.78[.]183 
205.234.232[.]196  
207.148.74[.]250 
216.155.157[.]136 
216.238.66[.]251 
216.238.71[.]49 
216.238.72[.]201 
216.238.74[.]95 
216.238.81[.]149 
216.238.85[.]220 
216.238.86[.]24