analyzingsshdinjector-apvrille2025

2025-10-26

Analyzing ELF/Sshdinjector.A!tr with a Human and Artificial Analyst

By Axelle Apvrille

February 04, 2025

https://www.fortinet.com/blog/threat-research/analyzing-elf-sshdinjector-with-a-human-and-artificial-analyst

Notes
sshdinjector
injection
SSH, sshd
DaggerFly (EVASIVE PANDA) espionage group
sshdinjector surfaced mid-November 2024
reverse engineering
ELF
Linux malware
libsshd.so
dropper
exfiltration
mainpasteheader, selfrecoverheader
persistence
command and control
“the dropper checks if it is being run under root privileges and, if not, exits. It then checks whether the host is infected by searching for a file named /bin/lsxxxssswwdd11vv containing the word WATERDROP.”
“If the host is not yet infected, it attempts to overwrite the legitimate binaries ls, netstat, and crond with infected binaries”
attribution via language (Chinese words for laughter: heihei, xixi)
– list of c2 commands
hard-coded IP addresses
“Communication with the C2 uses its own protocol. All packets include a hard-coded UUID (a273079c-3e0f-4847-a075-b4e1f9549e88), an identifier (afa8dcd81a854144), and the response to the command.”
Radare2
r2ai radare2 extention
generative AI
disassembler
iz – r2 command to search strings
AI output details often incorrect
decompiler output is correct, but often hard to read
AI hallucination
AI extrapolation
MAC address
AI omissions
– hash IoCs

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