PAPERMILL Hackers Abuse Signed Notepad++ to Deploy VenomRAT in Tax Audit Attacks
PAPERMILL phishing campaign abuses a signed Notepad++ copy and tax-audit lures to deploy VenomRAT against targets in India.
JUMPSEC tracks PAPERMILL as an emerging cluster whose emails pass SPF, DKIM, and DMARC and deliver tax-audit themed disk images. The mounted image pairs a legitimately signed, renamed executable with a rogue libcurl.dll for DLL sideloading, then uses a Donut shellcode loader to run VenomRAT 6.0.3 in memory with hidden VNC, data-stealing, and file-grabbing capabilities. The loader includes anti-analysis checks and RunOnce persistence, and lures plus China-connected infrastructure overlap with the Silver Fox ecosystem, though attribution remains unconfirmed.
xHunt Campaign: Attacks on Kuwait Shipping and Transportation Organizations
xHunt deployed custom backdoors Hisoka, Killua, Gon, and EYE against Kuwait shipping and transportation organizations, using DNS tunneling and email-draft C2 channels.
Unit 42 observed the xHunt campaign targeting Kuwait transportation and shipping organizations between May and June 2019, installing backdoors named after characters from the anime Hunter x Hunter, including Hisoka, Killua, Sakabota, and Netero. The tools use HTTP and DNS tunneling for C2, and Hisoka v0.9 added an unusual email-based C2 channel that abuses Exchange Web Services with stolen credentials to exchange email drafts. The Gon tool provides port scanning, file transfer, screenshots, remote command execution, and RDP session creation, while EYE acts as a cleanup failsafe if a legitimate user logs in. Related activity targeting Kuwait between July and December 2018 was reported by IBM X-Force IRIS, suggesting the campaigns are likely related.
Home & Small Office Wireless Routers Exploited to Attack Gaming Servers
Unit 42 details an updated Gafgyt botnet variant exploiting Zyxel, Huawei, and Realtek router vulnerabilities to recruit devices for DoS attacks on gaming servers.
Unit 42 researchers identified an updated Gafgyt variant derived from the JenX botnet that combines three remote code execution exploits: CVE-2017-18368 (Zyxel P660HN-T1A), CVE-2017-17215 (Huawei HG532), and CVE-2014-8361 (Realtek RTL81XX chipset). Shodan scans show more than 32,000 wireless routers worldwide potentially vulnerable to these exploits. The exploits act as droppers, pulling architecture-specific binaries from a malicious server (185.172.110.224), and the botnet performs denial-of-service attacks against gaming servers, most notably Valve Source engine servers.
Tick Group Weaponized Secure USB Drives to Target Air
Unit 42 says the Tick group weaponized South Korean certified secure USB drives with SymonLoader malware to reach air-gapped Windows XP systems.
Unit 42 discovered that the Tick cyberespionage group, which targets Japan and South Korea, compromised an ITSCC-certified secure USB drive made by a South Korean defense company and used a new loader named SymonLoader to extract a hidden executable from these drives. SymonLoader only infects Windows XP and Windows Server 2003, suggesting deliberate targeting of legacy air-gapped systems used by government and defense organizations. The group also delivered HomamDownloader and SymonLoader via Trojanized Korean and Japanese software sent as spearphishing attachments. Unit 42 believes the attacks occurred multiple years ago and that this malware is not part of an active campaign.