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Threat Brief: Maze Ransomware

Unit 42 issued a threat brief on Maze ransomware, noting an uptick across industries and exploitation of Pulse VPN and IE flaws for initial access.

Palo Alto Networks detected an uptick in Maze ransomware samples across finance, healthcare, government, and other sectors. Maze, a variant of ChaCha ransomware first seen in May 2019, is distributed via weaponized Word/Excel attachments and the Spelevo exploit kit leveraging CVE-2018-15982 and CVE-2018-4878, and has used CVE-2019-11510 (Pulse VPN) and CVE-2018-8174 (Internet Explorer). Operators establish a foothold, escalate privileges, move laterally, and exfiltrate files before encryption for extortion leverage.

Palo Alto Unit 42 · 29d agoRansomware in the wildCVE-2018-15982CVE-2018-4878CVE-2019-11510+1 CVEs

Cortex XDR™ Detects New Phishing Campaign Installing NetSupport Manager RAT

Cortex XDR threat hunters uncovered a phishing campaign delivering the NetSupport Manager RAT via a fake password-protected NortonLifelock Word document.

Unit 42 identified a January 2020 phishing campaign using a Microsoft Word document disguised as a password-protected NortonLifelock file. Enabling macros triggered an obfuscated command that built alpaca.bat in the temp directory, which used msiexec to download an MSI payload from quickwaysignstx.com, filtered on the Windows Installer user-agent string. The payload installed a PowerShell script and the campaign, which has delivered NetSupport Manager RAT since at least 2018, showed related activity dating back to early November 2019.

Palo Alto Unit 42 · 29d agoPhishing & fraud in the wild1

Threat Assessment: Ryuk Ransomware

Unit 42 assesses Ryuk ransomware amid a CISA/FBI/HHS alert on threats to U.S. healthcare, including the UHS attack that disrupted hospital operations.

A joint CISA, FBI, and HHS alert on October 28, 2020 warned of an imminent threat to U.S. healthcare from operators deploying Trickbot and Ryuk ransomware. Universal Health Services reported a Ryuk attack that disrupted all U.S. UHS sites for weeks, with similar incidents at hospitals in Oregon and New York. Ryuk typically arrives after Trickbot or BazaLoader infections delivered via malicious email, and operators enumerate networks with PowerShell and WMI before encryption. The Trickbot Anchor_DNS module performs DNS tunneling for C2, using connectivity checks to benign domains like ipinfo.io and checkip.amazonaws.com.

Palo Alto Unit 42 · 29d agoRansomware in the wild

Threat Brief: OWASSRF Vulnerability Exploitation

Unit 42 details active exploitation of Exchange SSRF flaws CVE-2022-41080/CVE-2022-41082 via the OWASSRF method, deploying the SilverArrow PowerShell backdoor.

Unit 42 documents OWASSRF, an exploit chain combining CVE-2022-41080 and CVE-2022-41082 to achieve remote code execution on Microsoft Exchange via Outlook Web Access, bypassing Microsoft's ProxyNotShell mitigations. Active exploitation was observed in late November and early December 2022, affecting at least eight organizations. Attackers authenticated to Exchange, then executed a PowerShell backdoor tracked as SilverArrow to create admin accounts, install AnyDesk, tunnel RDP via PuTTY Link, and dump LSASS memory for credential theft. Exploitation is isolated rather than mass-scale because authentication is required.

Threat Brief: Atlassian Confluence Remote Code Execution Vulnerability (CVE-2022

Unauthenticated Confluence RCE CVE-2022-26134 was exploited in the wild; Volexity observed intrusions and Cerber ransomware on unpatched servers.

Volexity identified exploitation of CVE-2022-26134, an unauthenticated remote code execution vulnerability in Atlassian Confluence Server and Data Center, during Memorial Day weekend 2022, with Atlassian issuing a patch. Cortex Xpanse found 19,707 potentially affected Confluence instances, concentrated in the US, Germany, China, and Russia, plus 1,251 end-of-life versions exposed. Unit 42 and Cortex Managed Threat Hunting observed successful exploitation leading to reconnaissance commands and a Cerber ransomware deployment that was blocked by Cortex XDR. A public PoC has increased exploitation risk.

Palo Alto Unit 42 · 29d agoExploit / PoC in the wildCVE-2022-26134

Keys to the Kingdom: Erlang/OTP SSH Vulnerability Analysis and Exploits Observed in the Wild

Attackers actively exploit CVE-2025-32433, a CVSS 10.0 unauthenticated RCE in Erlang/OTP SSH, heavily targeting OT and critical infrastructure networks.

CVE-2025-32433 enables unauthenticated RCE in Erlang/OTP's SSH daemon via SSH connection protocol messages (codes >= 80) processed before authentication, affecting versions before OTP-27.3.3, OTP-26.2.5.11 and OTP-25.3.2.20. Unit 42 recorded a spike in exploitation between May 1-9, 2025, with 70% of detections on firewalls protecting OT networks, disproportionately affecting healthcare, agriculture, media and high technology. Observed payloads bind TCP-connected shells or launch Bash reverse shells to hosts like 146.103.40.203:6667, with randomized DNS lookups under dns.outbound.watchtowr.com indicating OAST-driven blind RCE validation.

Palo Alto Unit 42 · 29d agoExploit / PoC in the wildCVE-2025-32433

Persistent Attempts at Cyberespionage Against Southeast Asian Government Target Have Links to Alloy Taurus

Alloy Taurus (GALLIUM) compromised Southeast Asian government networks from 2022 to 2023 using Exchange web shells and undocumented .NET backdoors Reshell and Zapoa.

Unit 42 tracked persistent multiwave intrusions at a Southeast Asian government starting in early 2022 and continuing through 2023, attributing the activity with moderate confidence to Alloy Taurus (aka GALLIUM), a Chinese state-aligned espionage group. Attackers exploited Exchange Server vulnerabilities to deploy web shells including China Chopper, then ran reconnaissance with Fscan and WebScan, created administrative accounts, and installed undocumented .NET backdoors named Reshell and Zapoa. They established resilience by installing SoftEther VPN, brute-forced Active Directory credentials with Kerbrute, and dumped credential stores with GoDumpLsass and LsassUnhooker. The campaign reflects long-term espionage tradecraft to maintain a foothold.

Palo Alto Unit 42 · 29d agoThreat actor in the wild1

CVE-2022-22965: Spring Core Remote Code Execution Vulnerability Exploited In the Wild (SpringShell) (Updated)

Attackers actively exploit Spring Framework RCE CVE-2022-22965 (SpringShell, CVSS 9.8) to deploy webshells; patches 5.3.18/5.2.20 shipped March 31, 2022.

CVE-2022-22965 enables unauthenticated remote code execution in the widely used Spring Framework (CVSS 9.8), which Unit 42 has observed being exploited in the wild. The flaw stems from getCachedIntrospectionResults exposing the class object during parameter binding, letting attackers manipulate the class loader to modify Tomcat logging and upload a JSP webshell. Public PoCs require JDK 9+, Tomcat, WAR packaging, and spring-webmvc or spring-webflux dependencies on Spring 5.3.0-5.3.17, 5.2.0-5.2.19, or older. Fixes shipped in Spring Framework 5.3.18 and 5.2.20; the related Spring Cloud Function flaw CVE-2022-22963 was patched March 29, 2022.

FrostyGoop’s Zoom-In: A Closer Look into the Malware Artifacts, Behaviors and Network Communications

Unit 42 dissects FrostyGoop OT malware, which sent Modbus TCP commands to disrupt heating for 600+ apartment buildings in Ukraine.

Palo Alto Unit 42 analyzed new FrostyGoop/BUSTLEBERM samples, the ninth known ICS-centric malware, first used against a Ukrainian municipal energy company by sending Modbus TCP commands to ENCO control devices. The attack caused a two-day heating outage affecting over 600 apartment buildings during sub-zero temperatures. The Go-compiled malware accepts Modbus register operations and timing parameters via command-line arguments or a JSON configuration file, uses an obscure open-source Modbus library, and checks the Windows BeingDebugged flag to evade debuggers. Unit 42 telemetry recorded over 1 million Modbus TCP devices exposed to the internet between September and October 2024.

Palo Alto Unit 42 · 27d agoMalware in the wild

Threat Brief: Ongoing Russia and Ukraine Cyber Activity

Ukrainian government sites were defaced via OctoberCMS CVE-2021-32648 while Microsoft-attributed actor DEV-0586 deployed destructive WhisperGate malware.

Unit 42 tracks January 2022 attacks against Ukrainian government websites that were defaced or made inaccessible, which Ukraine attributed to Russia. Attackers exploited CVE-2021-32648, an account takeover flaw in OctoberCMS prior to 1.0.472, by submitting a boolean true as the password reset code to bypass validation. Separately, WhisperGate malware, attributed by Microsoft to DEV-0586, disabled Windows Defender and corrupted files across multiple Ukrainian organizations, using a ransomware-appearing first stage and an HTTPS-beaconing second stage with LOLBINs and anti-analysis techniques.

Palo Alto Unit 42 · 29d agoThreat actor in the wildCVE-2021-326481

Threat Brief: 3CXDesktopApp Supply Chain Attack (Updated)

Trojanized 3CXDesktopApp installers for Windows and macOS loaded RC4-encrypted shellcode delivering a backdoor to hundreds of thousands of 3CX users.

Threat actors compromised the 3CXDesktopApp build process, adding malicious libraries (ffmpeg.dll, d3dcompiler_47.dll) to installers downloaded from the developer's website. The Windows MSI loader decrypts embedded shellcode with RC4, sleeps for a random 1-4 weeks, then beacons to C2 hidden in icon files on GitHub. Unit 42 fingerprinted 247,277 IPs across 199 countries using 3CX applications and blocked shellcode execution at 127 Cortex XDR customers between March 9-30, 2023.

Palo Alto Unit 42 · 29d agoThreat actor in the wild1

Stately Taurus Activity in Southeast Asia Links to Bookworm Malware

Unit 42 links Stately Taurus APT activity in ASEAN region and Myanmar to the decade-old Bookworm malware family via infrastructure overlaps.

Unit 42 connected Stately Taurus (aka Mustang Panda) espionage activity targeting ASEAN-affiliated organizations and Myanmar to the Bookworm malware family, first published in 2015. Earlier attacks delivered the PubLoad stager via DLL sideloading, with a PubLoad variant communicating with C2 at 123.253.32[.]15 while mimicking Windows Update URLs. Three previously unreported loader samples from 2021-2022 used UUID-decoded shellcode loaded via heap allocation and API callbacks, ultimately decrypting and loading Bookworm DLLs. A ToneShell backdoor variant shared debug paths with Bookworm loaders, and the January 2024 CSIRT CTI post corroborated the Myanmar attacks.

Palo Alto Unit 42 · 29d agoThreat actor in the wild

Threat Assessment: Egregor Ransomware

Unit 42 assesses Egregor ransomware, a Sekhmet variant likely run by former Maze affiliates using Qakbot, IcedID, and Ursnif for initial access.

Since September 2020, Unit 42 observed Egregor ransomware attacks across the U.S., Europe, Asia-Pacific, and Latin America, coinciding with the Maze team's shutdown announcement. Egregor, a variant of the Sekhmet family, uses commodity malware such as Qakbot, IcedID, and Ursnif for initial access, followed by scripts that modify firewalls, enable RDP, and deploy Cobalt Strike for reconnaissance and exfiltration. A PowerShell script uninstalls the McAfee agent and downloads the Egregor DLL via BITS, executed with the -passegregor10 key. Victims face a three-day ransom deadline before exfiltrated data is published on the Egregor Hall of Shame leak site.

Palo Alto Unit 42 · 29d agoRansomware in the wild

Automatically Detecting DNS Hijacking in Passive DNS

Unit 42's machine learning pipeline detected 6,729 DNS hijacking events between March and September 2024, hitting political parties, ISPs, and universities.

Unit 42 processes roughly 167 million new DNS records daily and applies a machine learning model using 74 features over 169 TB of passive DNS and geolocation data to flag hijacked domains. From March to September 2024 the pipeline screened over 29 billion records and classified 6,729 as DNS hijacking, averaging 38 detections per day; a new model detects hijacks in customer traffic within about 10 minutes. Notable cases include a Hungarian political party's hijacked domain, defacement of a large utility company and ISP, and university and research center domains repurposed for illicit gambling. DNS hijacking typically relies on stolen registrar or DNS provider credentials or cache poisoning, enabling MitM attacks, phishing, drive-by downloads, and scams.

Palo Alto Unit 42 · 29d agoResearch in the wild

Untracked Nightmares: The Threats Hiding Behind Commodity Infrastructure

Unit 42 exposes CL-CRI-1171, a pay-per-install network spreading malware like Insomnia RAT via YouTube channels and SEO poisoning for over two years.

Palo Alto Networks Unit 42 details CL-CRI-1171, a cybercrime cluster operating a pay-per-install (PPI) marketplace that has delivered multiple malware families for at least two years. The group used at least eleven YouTube gaming channels with hundreds of thousands of followers, plus SEO poisoning promoting trojanized software such as a Bluetooth driver and WinDirStat, infecting gamers and corporate endpoints including critical infrastructure and government entities. A single shared loader delivered payloads including Insomnia RAT, ARKTunnel, Docro Hijacker, GCleaner and Socks5Systemz between July 2025 and April 2026, with more than 10,000 distinct loader samples and over 200 rotating C2 domains identified. YouTube terminated the malicious channels after Unit 42 notified the platform.

Palo Alto Unit 42updated · 4d agofirst · 6d agoMalware in the wild 2 sources1

Attackers Expose Ongoing AI Tool Use Targeting Organizations in Latin America

Unit 42 documents two AI-assisted intrusion campaigns against Latin American government, utility, and financial organizations using LLM-orchestrated tooling.

Palo Alto Networks Unit 42 tracks two ongoing intrusion clusters, CL-CRI-1131 (Mexican transportation, federal ministries, municipal water utilities) and CL-CRI-1163 (Brazilian financial sector), both using living-off-the-land techniques, SOCKS5 relays, and custom RATs. The attackers appear to orchestrate operations via commercial LLMs like Claude and GPT-4.1, evidenced by iterative batch scripts and AI-generated tunneling tool naming. The Mexican campaign (also reported as Operation Escaneo by CloudSEK) exfiltrated sensitive data via dynamic-DNS infrastructure with rotated multi-SAN TLS certificates between February and June 2026. This signals broader adoption of AI-enhanced operations by diverse threat groups in the region.

Palo Alto Unit 42 · 12d agoThreat actor in the wild1

ApateWeb: An Evasive Large-Scale Scareware and PUP Delivery Campaign

Unit 42 uncovers ApateWeb, a campaign using over 130,000 domains and multilayered redirects to deliver scareware, adware and PUPs to millions of users.

Unit 42 discovered ApateWeb, a large-scale campaign using a network of more than 130,000 domains to deliver scareware, potentially unwanted programs, adware including a rogue browser and browser extensions, and scam pages. The campaign uses a three-layer structure with deceptive emails as the entry point, centralized victim tracking via UUIDs, intermediate adware or anti-bot redirections, and evasion tactics such as cloaking, bot detection error pages, and wildcard DNS abuse. Activity spiked since August 2022, with several hundred attacker-controlled sites remaining in Tranco's top 1 million rankings and millions of monthly hits; Unit 42 blocked an estimated 3.5 million sessions across 74,711 devices in November 2023.

Palo Alto Unit 42 · 29d agoPhishing & fraud in the wild

Another Apache Log4j Vulnerability Is Actively Exploited in the Wild (CVE-2021

Apache Log4j 2 RCE CVE-2021-44228 is actively exploited via crafted JNDI lookups; Palo Alto Unit 42 urges upgrading to Log4j 2.17.1.

Unit 42 details CVE-2021-44228, an easily exploited remote code execution flaw in Apache Log4j 2 where attacker-supplied JNDI lookups in logged user input cause payload download and execution. Massive internet-wide scanning for unpatched systems has begun, with observed follow-on activity including information stealing, Cobalt Strike delivery, and coinmining. The recommended fix is Log4j 2.17.1, which also patches CVE-2021-45046, CVE-2021-45105, and CVE-2021-44832. Widely used Java software including Apache Struts, Solr, Druid, Flink, ElasticSearch, and Spring Boot is affected.

Palo Alto Unit 42 · 29d agoExploit / PoC in the wildCVE-2021-44228CVE-2021-45046CVE-2021-45105+3 CVEs

Exploring the Latest Mispadu Stealer Variant

Unit 42 found a new Mispadu infostealer variant targeting Mexican users via malicious .url files exploiting the SmartScreen CVE-2023-36025 bypass.

Unit 42 discovered a new variant of Mispadu Stealer, a Delphi-based banking trojan first reported in 2019, found while hunting for the Windows SmartScreen bypass CVE-2023-36025. The campaign uses crafted .url files referencing UNC network-share paths with an HTTP port (@80) that forces payload retrieval over WebDAV via rundll32.exe, avoiding SmartScreen warnings. Analyzed samples (~4 KB, compiled 2023-11-12) predate the CVE publication, and ZIP payloads were likely distributed as email attachments, primarily targeting users in Mexico.

Palo Alto Unit 42 · 29d agoMalware in the wildCVE-2023-360251

Unit 42 Researchers Discover Multiple Espionage Operations Targeting Southeast Asian Government

Unit 42 attributes three espionage clusters targeting a Southeast Asian government to Stately Taurus, Alloy Taurus, and Gelsemium APTs.

Unit 42 investigated espionage attacks starting in late 2022 against multiple governmental entities in a Southeast Asian country, including critical infrastructure, public healthcare, financial administrators, and ministries. Analysis revealed three distinct clusters: CL-STA-0044 attributed to Stately Taurus (Mustang Panda), CL-STA-0045 to Alloy Taurus (GALLIUM), and CL-STA-0046 to Gelsemium. The first cluster used a ToneShell backdoor variant, ShadowPad, China Chopper web shells, Impacket, and credential dumping tools across roughly Q1 2021 to Q3 2023. All three operated with distinct tools, infrastructure, and long-term surveillance tradecraft consistent with APTs.

Palo Alto Unit 42 · 29d agoThreat actor in the wild

Hackers Abuse YouTube Gaming Channels and SEO Poisoning to Deploy RATs and Chrome Hijacker

Unit 42 exposed CL-CRI-1171, a pay-per-install operation using YouTube gaming channels and SEO poisoning to deliver RATs and a Chrome hijacker.

Palo Alto Networks Unit 42 identified over 10,000 OfferLoader samples and 11 YouTube channels pushing trojanized installers via gaming lures and SEO-poisoned searches for tools like WinDirStat and Bluetooth drivers. Trojanized Inno Setup installers spawn three payload branches: Insomnia RAT (dual Node.js/Python backdoor that disables Microsoft Defender), ARKTunnel (undocumented RAT hiding its payload in a bitmap image and tunneling TCP/UDP), and Docro Hijacker (alters Chrome protected preferences to hijack search and affiliate links). The pay-per-install model sells each infection to multiple buyers, reaching gamers as well as corporate and government endpoints.

Cyber Security News · 2d agoMalware in the wild1

Hackers Use LLMs to Generate Exploit Scripts and Automate Post-Exploitation Across Latin America

Unit 42 says Latin American attackers used LLMs to automate post-exploitation in campaigns hitting Mexican government, water utilities, and Brazilian financial firms.

Unit 42 identified two campaigns in Latin America whose operators used commercial LLMs (Claude, GPT-4.1) behind a self-hosted NextChat interface to generate and debug post-exploitation scripts. Cluster CL-CRI-1131 compromised a transportation organization, Mexican federal ministries, and water utilities in Mexico and Ecuador, using native Windows tools and Volume Shadow Copies to dump the SAM registry hive and NTDS.dit. Cluster CL-CRI-1163 targeted Brazilian financial organizations with job-themed phishing, custom RATs, and a Go-based reverse SOCKS5 tunneling utility called SockTz, with nine versions deployed within roughly two hours. Trend Micro tracks related AI-augmented activity as SHADOW-AETHER-040 and SHADOW-AETHER-064.

GBHackersupdated · 6d agofirst · 6d agoThreat actor in the wild 2 sources1

A Deep Dive Into Attempted Exploitation of CVE-2023

Mirai-like botnet scans exploit TP-Link EOL router flaw CVE-2023-33538 after CISA KEV addition, though observed exploit code is flawed.

Unit 42 observed large-scale automated scans attempting to exploit CVE-2023-33538 in end-of-life TP-Link TL-WR940N, TL-WR740N and TL-WR841N routers after CISA added the flaw to its KEV catalog in June 2025. HTTP GET requests inject commands via the ssid1 parameter at the /userRpm/WlanNetworkRpm endpoint to download and execute an arm7 ELF binary, a Mirai variant related to the Condi IoT botnet. Firmware emulation and reverse engineering showed the observed exploits are flawed and would fail, but the underlying vulnerability is real and successful exploitation requires authentication to the router's web interface. TP-Link confirmed the devices are end-of-life with no patches available and recommends replacing units and eliminating default credentials.

Palo Alto Unit 42 · 27d agoExploit / PoC in the wildCVE-2023-335381