Hackers Use SANSAR Linux Malware to Hide Crypto Mining by Faking 0% GPU Usage

Blog WriterCybersecurity News - Original News Source is cybersecuritynews.com


Hackers are hiding cryptocurrency mining on Linux GPU servers by changing the readings administrators use to spot heavy workloads.

The toolkit combines a Rust-based controller called SANSAR, a kernel rootkit, and a modified NVIDIA monitoring library that reports 0% GPU utilization while mining continues in the background.

The intrusion reached three Linux GPU hosts through an exposed Ray job agent. Ray supports distributed computing, including AI training and inference, making these systems valuable targets.

Unlike campaigns involving fake utility download traps, this attack entered through infrastructure that accepted remote computing jobs without authentication.

Researchers from Elastic Security Labs identified the activity as REF3364 in a November 12, 2026, technical analysis of SANSAR.

Their findings describe coordinated tools for mining, hiding processes, maintaining access, and opening remote shells—not simply a miner running unnoticed.

Hackers Use SANSAR Linux Malware

The deception targets NVIDIA Management Library, or NVML, the interface used by monitoring tools such as nvidia-smi. The attacker’s wrapper forwards requests to the genuine NVIDIA library, then changes selected results before returning them.

GPU utilization becomes zero, while temperature and power readings are replaced with random values between 36–46 degrees Celsius and 100–200 watts.

This makes apparently normal monitoring output unreliable. The GPU is not necessarily idle; the software reporting its activity has been altered.

SANSAR can also rebuild and reinstall the wrapper from recovered source files, giving the operator a way to maintain the modified monitoring layer.

Execution flow of SANSAR diagram (Source - Elastic)
Execution flow of SANSAR diagram (Source – Elastic)

A separate kernel rootkit hides selected processes, files, and socket entries. It intercepts directory listings and other system operations, removing matching records or returning errors when tools inspect hidden processes.

Similar Linux rootkit mining attacks have used kernel-level concealment, but this toolkit adds falsified GPU measurements to obscure resource use.

SANSAR itself supervises publicly available mining software rather than performing every mining task internally. Its CPU branch uses XMRig, while its GPU branch launches SRBMiner-MULTI.

The controller supplies pool addresses, wallet or login details, algorithms, and other settings. Elastic found no hardcoded fallback pool or wallet in those launch paths.

Exposed Ray Jobs Enable Persistent Remote Access

Recorded activity began with external probes on October 22, followed by a GPU inventory query on October 24. On October 25, the attacker submitted a Python reverse-shell job.

Although the Ray head-node dashboard listened only on localhost, the job agent remained internet-accessible and accepted unauthenticated submissions. The initial shell ran under the account owning the Ray session. The attacker then added an SSH key for continued access.

After obtaining root, the operator installed the toolkit, built its kernel module through Dynamic Kernel Module Support, and added an early-boot loader. Elastic’s account does not explain the precise method used to obtain root.

Control extends beyond mining. SANSAR communicates over Tor and supports interactive Bash shells, miner configuration changes, output forwarding, and TCP SYN traffic generation.

Its shell setup suppresses saved command history. These capabilities make the compromise broader than stolen computing capacity alone.

A separate backdoor retrieves its controller address from an Ethereum smart contract, then connects directly over TCP. This creates another route for shell access.

Earlier Discord controlled mining campaigns also combined mining with remote control, although their communication methods differed from this intrusion.

For defenders, Elastic highlights two priorities: check who can submit Ray jobs and verify whether GPU monitoring libraries have changed.

A zero reading from an altered library cannot establish that a server is clean. Investigations should also account for persistent access and kernel-level hiding rather than treating the visible miner as the entire infection.

Indicators of compromise (IoCs):-

Type Component or role Indicator
SHA-256 SANSAR orchestrator 00c9ac44291f83c72d54302e99d155a3e26d02225a3e516764d5833a99657c9e
SHA-256 XMRig, named kurt 96fc528ca5e7d1c2b3add5e31b8797cb126f704976c8fbeaecdbf0aa4309ad46
SHA-256 SRBMiner-MULTI, named tilki acc706afc9322a3eae1ef49049749e0a7c9f1a123895ac56dc8a289beb2fb5b7
SHA-256 Lyrebird transport helper cc1ad7f14777a098ccc91fd4e8f6143da14418c2b6fdf23b7f8f6b3d1b0b7f1d
SHA-256 Modified NVML wrapper 675c24728f87f7aa0fa07527027c95c24c246049c65eaef89270ab04ea50a180
SHA-256 acpi_thermal_mgr.ko rootkit 6ba1aa275e0e2826e8b48b36473539ca56cbdc41f429e539a45f8532b084d7a4
SHA-256 netns backdoor df8ab6fd699e6ae90e63e9696bae8f01342708bafc2ed88af414337e4f237194
Onion endpoint SANSAR controller efxisnqldelyr5ra25oqfrsut54b34g26e7zrsiuupsoekjof2gho2id.onion:9051
Ethereum contract Backdoor controller discovery 0x43eb291f56688c63c93e8a93c4591fc997cf6349
Contract selector Controller lookup 0x6ded96e7
TCP port Backdoor controller connection 8080

Note: IP addresses and domains are intentionally Qdefanged (e.g., [.]) to prevent accidental resolution or hyperlinking. Re-fang only within controlled threat intelligence platforms such as MISP, VirusTotal, or your SIEM.

Give your SOC the alert context on the latest threats to stop incidents quickly -> Integrate Threat Intel from 16K SOCs

The post Hackers Use SANSAR Linux Malware to Hide Crypto Mining by Faking 0% GPU Usage appeared first on Cyber Security News.