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Malware

R77 rootkit

r77 rootkit is a Windows rootkit observed as a final-stage payload in multiple criminal intrusion chains. The provided content links it to ClickFix-style social-engineering campaigns in which victims are tricked by fake CAPTCHA or verification pages into executing obfuscated commands, often via the Microsoft-signed SyncAppvPublishingServer.vbs App-V script and in-memory PowerShell stages. In these campaigns, the final shellcode loader can deploy malware including Amatera Stealer, Lumma Stealer, Xworm, AsyncRAT, and the r77 rootkit. One cited campaign delivered the r77 rootkit via Discord-themed ClickFix lures under the name OBSCURE#BAT. The content also notes r77 rootkit bundled with the XMRig cryptominer, including a sample protected by the PackXOR private packer together with SilentCryptoMiner (SHA-256: b86612a6d62a1789031248bdb732b8bff51acaeaa687c3559f0980560a8abf2f). Another mention references an 'r77 Rootkit Bot' in a JDownloader supply-chain attack that killed antivirus products, but no further high-confidence technical details are provided in the supplied material. Based on the content, r77 rootkit is associated with financially motivated malware delivery activity, Windows-focused execution chains, and use alongside stealers, RATs, and cryptomining payloads.

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MITRE ATT&CK

Techniques & procedures

6 distinct techniques documented for this family, organized by ATT&CK tactic.

Initial Access

1 technique
T1195.002Compromise Software Supply ChainEvidence1

On May 6, 2026, attackers compromised the official JDownloader website and swapped download links to serve trojanized installers.

Persistence

2 techniques
T1112Modify RegistryEvidence1

The dropper writes the bot's initial configuration to HKCU\SOFTWARE\Python... Registry persistence — stores the stager assembly as a binary blob in HKLM\SOFTWARE\$77stager and reloads it at every boot via .NET reflection.

T1543.003Windows ServiceEvidence1

Service creation — installs a Windows service ( $77svc ) to ensure the rootkit survives reboots independently of the registry mechanism.

Privilege Escalation

2 techniques
T1055.001Dynamic-link Library InjectionEvidence1

Reflective DLL injection — injects the r77 hooking DLLs (32-bit and 64-bit variants) into winlogon.exe.

T1543.003Windows ServiceEvidence1

Service creation — installs a Windows service ( $77svc ) to ensure the rootkit survives reboots independently of the registry mechanism.

Stealth

3 techniques
T1014RootkitEvidence2

The rootkit stager is a 176 KB native x86 PE based on the open-source r77 rootkit... These DLLs hook Windows API functions to hide any process, file, or registry key whose name starts with the $77 prefix.

T1027Obfuscated Files or InformationEvidence2

Inside, it wraps the legitimate JDownloader installer alongside an XOR-encrypted second-stage PE... Stage 2's strings are all XOR-obfuscated with the same fywo key used for its resources.

T1055.001Dynamic-link Library InjectionEvidence1

Reflective DLL injection — injects the r77 hooking DLLs (32-bit and 64-bit variants) into winlogon.exe.

Defense Impairment

1 technique
T1112Modify RegistryEvidence1

The dropper writes the bot's initial configuration to HKCU\SOFTWARE\Python... Registry persistence — stores the stager assembly as a binary blob in HKLM\SOFTWARE\$77stager and reloads it at every boot via .NET reflection.

INDICATORS OF COMPROMISE

IOCs tracked for this family

12 indicators attributed across vendor reports, sandbox runs, and researcher write-ups. Full values are available in Mallory.

View more in app
Network
9 tracked

IPs, domains, and DNS infrastructure linked to this family.

Hashes
3 tracked

File hashes (MD5, SHA-1, SHA-256) from samples and reports.

TypeValueLatest sighting
domain●●●●●●●●●●●●View more in app8 days ago
domain●●●●●●●●●●●●View more in app1 month ago
domain●●●●●●●●●●●●View more in app1 month ago
hash.sha256●●●●●●●●●●●●View more in app1 month ago
ip.v4●●●●●●●●●●●●View more in app1 month ago
ip.v4●●●●●●●●●●●●View more in app1 month ago
What this page doesn’t show

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IOC matching12

Match every observed IP, domain, and hash against your live telemetry.

Threat actor attribution

Named campaigns wielding this family, with evidence pinned to each claim.

Exploited vulnerabilities

CVEs this family uses for access and lateral movement.

Detection signatures

YARA, Sigma, Snort, and vendor rules, auto-deployed to your SIEM.

MITRE ATT&CK mapping6

Every documented technique, ranked by evidence weight.

Researcher chatter

Reddit, Mastodon, and CTI community discussion around this family.