All news with #defense evasion tag

🔒 Attackers are deploying a persistent backdoor using OpenSSH and a customized Tor hidden service to target defense-related organizations in Russia and Belarus. The Operation SkyCloak campaign uses weaponized ZIP attachments and LNK-triggered PowerShell stagers that perform sandbox evasion and write an .onion hostname into the user's roaming profile. Persistence is established via scheduled tasks that run a renamed sshd.exe and a bespoke Tor binary using obfs4, enabling SSH, SFTP, RDP and SMB access over Tor.

🛡️ Rhysida ransomware operators have shifted to malvertising and the abuse of Microsoft Trusted Signing certificates to slip malware past defenses. By buying Bing search ads that point to convincing fake download pages for Microsoft Teams, PuTTY and Zoom, they deliver initial access tools such as OysterLoader (formerly Broomstick/CleanUpLoader) and Latrodectus. Signed, packaged binaries evade static detection and often run without scrutiny on Windows endpoints.

🔒 During economic downturns, organizations must preserve cybersecurity with constrained budgets by prioritizing risk-based controls, hardening existing systems, and blending open- and closed-source tools. The blog recommends defense-in-depth, isolating legacy hardware, disabling unnecessary features, and tuning EDR/AV, logging, and network filters to reduce exposure. It also advises retaining skilled incident response partners and investing selectively in early-to-mid career talent to maintain long-term resilience.

🛡️ Trend Micro reports that the Agenda (Qilin) ransomware group is running a Linux-based encryptor on Windows hosts to evade Windows-only detections. The actors abused legitimate RMM and file-transfer tools — including ScreenConnect, Splashtop, Veeam, and ATERA — to maintain persistence, move laterally, and execute payloads. They combined social engineering, credential theft, SOCKS proxy injection, and BYOVD driver tampering to disable EDR and compromise backups, impacting more than 700 victims since January 2025.

🔒 Qilin (aka Agenda, Gold Feather, Water Galura) has sharply increased operations in 2025, claiming dozens of victims monthly and peaking at 100 leak-site postings in June. Cisco Talos and Trend Micro analyses show affiliates gain initial access via leaked admin credentials, VPN interfaces and RDP, then harvest credentials with tools like Mimikatz and SharpDecryptPwd. Attackers combine legitimate remote-management software (for example AnyDesk, ScreenConnect, Splashtop) with a BYOVD vulnerable driver to disable defenses, exfiltrate data, and deploy a Linux ransomware binary on Windows systems before encrypting files and removing backups.

🚨 Researchers uncovered a malvertising campaign that uses Google Ads to surface convincing fake Homebrew, LogMeIn, and TradingView download sites targeting macOS developers. The pages prompt victims to copy a curl command into Terminal, but the clipboard often contains a base64-encoded installer that decodes and runs an install.sh payload. That script removes quarantine flags, bypasses Gatekeeper, and delivers infostealers that check for analysis environments before executing. Operators deploy AMOS and Odyssey, which harvest browsers, wallets, and credentials; users are urged not to paste unknown commands into Terminal.

🔐 Microsoft Deputy CISO Raji Dani outlines the importance of hardening customer support tools and identities to reduce the risk of lateral movement and data exposure. The post recommends dedicated, isolated support identities protected by Privileged Role MFA and strict device controls. It advocates case-based RBAC with just-in-time and just-enough access, minimizing service-to-service trust, and deploying robust telemetry to speed detection and response. These layered controls apply to in-house teams and third-party providers.

🛡️ReliaQuest attributes a campaign to China-linked group Flax Typhoon that compromised a public-facing ArcGIS server by converting a Java Server Object Extension (SOE) into a gated web shell, maintaining access for over a year. The attackers embedded a hard-coded key and hid the backdoor in system backups to survive full system recovery. They uploaded a renamed SoftEther executable (bridge.exe), created a "SysBridge" service to persist, and used an outbound HTTPS VPN bridge to extend the victim network for covert lateral movement. Investigators observed credential theft, admin account resets, and extensive living-off-the-land activity to evade detection.

🔒 DarkAtlas researchers warn that APT groups are leveraging legitimate RMM platforms to gain initial access, increasingly favoring ScreenConnect as it evades basic detection. Attackers abuse features like unattended access, VPN, REST API and file transfer, deploy in-memory installers that leave little disk artefacts, and register persistent services such as ScreenConnect.WindowsClient.exe. Defenders should monitor invite links, config files, in-memory activity and specific event IDs for effective DFIR.

🔒 Threat actors are abusing Velociraptor, an open-source DFIR tool, to support ransomware operations attributed to Storm-2603. Attackers exploited on-premises SharePoint ToolShell flaws to deploy an outdated Velociraptor build (0.73.4.0) vulnerable to CVE-2025-6264, enabling privilege escalation and remote command execution. After lateral movement and creation of domain admin accounts, the group tampered with GPOs, disabled real‑time protection, and staged exfiltration before deploying Warlock, LockBit, and Babuk. Vendors caution that legitimate collection and orchestration capabilities can be repurposed by adversaries.

⚠️Researchers have observed threat actors leveraging the open-source DFIR tool Velociraptor to maintain persistent remote access and deploy ransomware families including LockBit and Babuk. Cisco Talos links the campaigns to a China-based group tracked as Storm-2603 and notes use of an outdated Velociraptor build vulnerable to CVE-2025-6264. Attackers synchronized local admin accounts to Entra ID, accessed vSphere consoles, disabled Defender via AD GPOs, and used fileless PowerShell encryptors with per-run AES keys and staged exfiltration prior to encryption.

🧯 Cisco Talos warns of extensive abuse of CSS to insert hidden “salt” — extraneous characters, comments and markup — into email preheaders, headers, attachments and bodies to evade detection. This hidden text salting technique is significantly more common in spam and malicious mail than in legitimate messages, undermining both signature and ML-based defenses. Talos advises detecting concealed content and, crucially, stripping or normalising that salt before passing messages to downstream engines, while also urging attention to longer-term strategic decision-making in cyber defense.

🧂 Cisco Talos documents growing abuse of CSS to insert visually hidden 'salt' into emails, a technique that undermines parsing and language-detection systems. Observed across preheaders, headers, attachments and bodies between March 1, 2024 and July 31, 2025, attackers use CSS properties (font-size, opacity, display, clipping) and zero-width characters to conceal irrelevant content. Talos recommends detection plus HTML sanitization and filters—examples include Cisco Secure Email Threat Defense—to strip or ignore invisible content before downstream analysis.

📎 BlackPoint researchers tracked a campaign that distributes credential-themed ZIP archives containing malicious Windows shortcut (.lnk) files. When opened, the shortcuts launch minimized, obfuscated PowerShell that downloads DLL payloads disguised as .ppt files, saves them to the user profile and invokes them via rundll32.exe. The dropper assembles commands from byte arrays, probes for antivirus processes and uses quiet flags to minimize visible indicators. Recommended mitigations include blocking LNKs in archives, enforcing Mark of the Web, denying execution from user-writable locations, and enabling PowerShell script block logging and AMSI.

🔒 LockBit 5.0 introduces faster ESXi drive encryption and enhanced evasion techniques, according to Trend Micro. The release includes Windows, Linux and VMware ESXi variants featuring heavy obfuscation, ETW patching, DLL reflection and hypervisor-targeted encryption designed to amplify impact. Researcher Jon DiMaggio describes the update as largely incremental fine-tuning and self-branding aimed at restoring affiliate trust after Operation Cronos.

🔍 Unit 42 uncovered Operation Rewrite, a March 2025 SEO poisoning campaign that deploys a native IIS implant called BadIIS to manipulate search engine indexing and redirect users to attacker-controlled scam sites. The implant registers request handlers, inspects User‑Agent and Referer headers, and proxies malicious content from remote C2 servers. Variants include lightweight ASP.NET page handlers, a managed .NET IIS module, and an all-in-one PHP front controller. Organizations can detect and block activity with Palo Alto Networks protections and should engage incident responders if compromised.

🔒 A new proof-of-concept named EDR-Freeze shows that Windows Error Reporting can be abused from user mode to suspend antivirus and EDR processes. The method leverages WerFaultSecure and the MiniDumpWriteDump API so the dumper pauses a target process and then the dumper itself is frozen, leaving the security agent inoperative without a kernel driver. Researcher TwoSevenOneThree validated the technique on Windows 11 24H2, describing it as a design weakness rather than a classic vulnerability, and defenders can monitor WER invocations or harden reporting components to mitigate the risk.

🛡️ Acronis researchers have uncovered a rare FileFix campaign that hides a second-stage PowerShell script and encrypted executables inside JPG images using steganography. Attackers employ multilingual, heavily minified phishing pages that mimic a Meta support flow and trick victims into pasting a payload into file upload address bars. An obfuscated PowerShell one-liner downloads images from Bitbucket, extracts and decrypts components, and executes a Go-based loader that deploys StealC. Organizations should combine user training with process blocking and monitoring to mitigate this evolving threat.

🔧 Microsoft has announced that the legacy WMIC command-line tool will be removed after systems are upgraded to Windows 11 25H2 and later. Administrators are advised to migrate scripts and automation to PowerShell or programmatic alternatives such as WMI's COM API or .NET libraries. The change affects only the WMIC client; the underlying WMI infrastructure remains supported. Microsoft says the removal reduces complexity and limits abuse of WMIC by threat actors.

🔒 HybridPetya is a newly identified UEFI bootkit that can bypass Secure Boot by exploiting CVE-2024-7344, enabling installation of malicious components into the EFI System Partition. ESET located a sample on VirusTotal and describes it as possibly a proof-of-concept, research project, or an early-stage criminal tool. The bootkit replaces the Windows bootloader, forces reboots to execute at startup, encrypts MFT clusters with Salsa20 while showing a fake CHKDSK, and then presents a ransom screen demanding a Bitcoin payment and a 32-character key to restore the bootloader and decrypt data.