Unveiling “sedexp”: A Stealthy Linux Malware Exploiting udev Rules
by Zachary Reichert
August 19. 2024
https://www.aon.com/en/insights/cyber-labs/unveiling-sedexp
Notes |
---|
Stroz Friedberg |
malware |
Linux malware |
Linux |
sedexp |
udev |
udev rules |
persistence |
evasion |
reverse shell |
MITRE ATT&CK |
udev persistence was not documented in ATT&CK |
financially motivated threat actor |
/dev |
Linux kernel |
device node |
hotplug |
USB |
etc/udev/rules.d |
lib/udev/rules.d |
udev rule format: ACTION, ENV{MAJOR}, ENV{MINOR}, RUN |
/dev/random |
memory modification for stealth |
webshell |
Apache |
changes process name to kdevtmpfs using prctl |
prctl |
blend in with legitimate processes |
readlink() |
/proc/self/exe |
threat intelligence |
credit card scraping |
OSINT |
online sandboxes had zero detections |
been in use since at least 2022 |
DFIR |
Samples |
---|
43f72f4cdab8ed40b2f913be4a55b17e7fd8a7946a636adb4452f685c1ffea02 |
94ef35124a5ce923818d01b2d47b872abd5840c4f4f2178f50f918855e0e5ca2 |
b981948d51e344972d920722385f2370caf1e4fac0781d508bc1f088f477b648 |