Atomic MacOS (AMOS) stealer infection, (Sun, Aug 2nd)
Introduction This diary provides indicators from an Atomic MacOS (AMOS) stealer infection that I generated in my lab on July 31st, 2026. This was distributed through a web page from getmacouscloud[.]com with instructions to paste text into a macOS Terminal window, supposedly for "macOS toolkit," but instead the text is a command to retrieve and install AMOS stealer malware. Of note, I ran the text in the Terminal window twice, because I wanted to make sure I retrieved copies of files in the host's /tmp directory before entering the user account password. This is why the initial infection traffic is repeated, and also likely why there are two different directories with the AMOS stealer malware persistent on my infected lab host. Images from the Infection Shown above: Website with instructions to copy and paste text into a Terminal window, supposedly for a "macOS toolkit" but actually for malware. Shown above: The malicious text pasted into a Terminal Window on a macOS host. Shown above: Files from my infected host's /tmp directory, showing data stolen and other info for AMOS stealer. Shown above: Examples of AMOS stealer persistent on my infected macOS host. Shown above: Traffic from the AMOS stealer infection filtered in Wireshark. Indicators of Compromise Traffic leading to the getmacouscloud[.]com page on Friday 2026-07-31: hxxps[:]//macostruecloud[.]xyz/?h=2f9548d041648a8030c040ae0e1e530b&z=304 macspheres[.]com - HTTPS traffic hxxps[:]//getmacouscloud[.]com/?FSSbmnNdviEDE5S?io=16vwsb0rgIiPNIgM URL from the base64 text provided by getmacouscloud[.]com for the initial download: hxxps[:]//render65[.]com/curl/f5509695dd98a9732378e5256d6235415d64d92194459bb08525c7ce5991a0c9 URLs from extracted from the payload returned from the initial download: hxxps[:]//grove-89[.]com/api/metrics/run?event=pasted hxxps[:]//render65[.]com/2kqYRM0DCrnyJgoS4gVLl_FHJRRdTUhGCbjyuYwpZ6c/m1/update AMOS stealer C2 traffic - HTTP POST requests over TCP port 80: hxxp[:]//188.166.78[.]138/api/metrics/run?event=started&stage=boot hxxp[:]//188.166.78[.]138/api/metrics/run?event=stage&stage=init_session hxxp[:]//188.166.78[.]138/api/metrics/run?event=stage&stage=messengers hxxp[:]//188.166.78[.]138/api/metrics/run?event=stage&stage=credentials hxxp[:]//188.166.78[.]138/api/metrics/run?event=stage&stage=browsers hxxp[:]//188.166.78[.]138/api/metrics/run?event=stage&stage=wallets hxxp[:]//188.166.78[.]138/contact hxxp[:]//188.166.78[.]138/api/metrics/run?event=stage&stage=resolve_auth hxxp[:]//188.166.78[.]138/api/metrics/run?event=stage&stage=local_data hxxp[:]//188.166.78[.]138/api/join/ hxxp[:]//188.166.78[.]138/api/bots/device-info hxxp[:]//188.166.78[.]138/api/tasks/ack hxxp[:]//188.166.78[.]138/api/feed/register AMOS stealer C2 traffic - examples of HTTP GET requests over TCP port 80: hxxp[:]//188.166.78[.]138/api/tasks/r3dqbX7fptIT-gXz--D_nw?v=2.1 hxxp[:]//188.166.78[.]138/api/feed/items/49359f77ebb4ffd9a95568d27a8ff3e7 SHA-256 hash: b9ec3261d633c289e51c5fa8842af4350efe68446df39cb995de82e0941d0f3c File size: 1,973 bytes File type: Paul Falstad's zsh script text executable, ASCII text File description: Initial file retrieved by malicious text in Terminal window SHA-256 hash: 13b868b3ea8b492e7fbab1ca04535c53d0930650185b5a082cd59c1974689cd5 File size: 1,227 bytes File type: Paul Falstad's zsh script text executable, ASCII text, with very long lines (315) File description: Script extracted from a gzip-compressed file from base64 text in the above file SHA-256 hash: 9f25ec533cb23d020e568fb771500d7776b1300f07119ad9d0876f4329ce22ab File size: 297,952 bytes File location: /tmp/helper File type: Mach-O universal binary with 2 architectures: x86_64 & arm64 SHA-256 hash: 0a03cf18de28017c0ea591dffc380a6b41fedd2acc3a39e901e58d9188c01836 File size: 438,656 bytes File location: /Users/[username]/Library/Application Support/.com.apple.accountsd/AccountsHelper File type: Mach-O universal binary with 2 architectures: x86_64 & arm64 SHA-256 hash: 01a0d5332b09bb299f7784bf0d0c43c4199269ed6a0712377279eeb999847d20 File size: 503,152 bytes File location: /Users/[username]/Library/Application Support/.com.apple.metadata.mds/mdworker_shared File type: Mach-O universal binary with 2 architectures: x86_64 & arm64 --- Bradley Duncan brad [at] malware-traffic-analysis.net
isc.sans.eduAug 2, 2026extracted