All news with #web shell tag

🔍 A single Microsoft Defender alert triggered an investigation that uncovered a persistent cyberthreat against retail customers. Attackers exploited unpatched SharePoint flaws CVE-2025-49706 and CVE-2025-49704 using obfuscated ASPX web shells while also compromising identities through self-service password reset abuse and Microsoft Entra ID reconnaissance. DART swiftly contained the intrusions—removing web shells, isolating Entra ID, deprivileging accounts, and recommending Zero Trust measures, MFA enforcement, timely patching, and EDR deployment.

🔒 CISA assisted a U.S. federal civilian executive branch agency after endpoint alerts showed threat actors exploiting CVE-2024-36401 in public-facing GeoServer instances to gain initial access. The actors operated undetected for roughly three weeks, deployed web shells and proxy/C2 tools, and moved laterally to a web and SQL server. CISA highlights urgent patching of KEV-listed flaws, exercising incident response plans, and improving EDR coverage and centralized logging.

🔍 Palo Alto Networks Unit 42 is tracking an SEO poisoning campaign dubbed Operation Rewrite that employs a native IIS implant called BadIIS. The module inspects User-Agent strings, identifies search engine crawlers, and fetches poisoned content from a remote C2 to inject keywords and links so compromised sites artificially rank for targeted queries. Unit 42 observed multiple tooling variants — lightweight ASP.NET handlers, a managed .NET IIS module, and an all‑in‑one PHP script — and reports a focus on East and Southeast Asia, particularly Vietnam.

🔍 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.

🔍 Researchers at ESET disclosed a previously undocumented campaign named GhostRedirector that has compromised at least 65 Windows servers mainly in Brazil, Thailand and Vietnam. The intruders deployed a passive C++ backdoor, Rungan, alongside a native IIS module, Gamshen, which selectively alters responses for Googlebot to perform SEO fraud. Initial access appears linked to SQL injection and abuse of xp_cmdshell, with subsequent PowerShell retrievals from a staging host.

🔍 ESET researchers identified GhostRedirector, a China-aligned threat group active since at least August 2024 that has compromised at least 65 Windows servers across multiple countries, notably Brazil, Thailand and Vietnam. The group deployed two novel tools: a C++ backdoor Rungan for remote command execution and a malicious IIS module Gamshen that manipulates search rankings to boost targeted sites. Operators also leveraged known privilege escalation exploits like BadPotato and EfsPotato to obtain administrator access and create persistent accounts. Organizations are advised to monitor IIS modules, patch promptly and audit high-privilege accounts and PowerShell activity.

🛡️ In March 2025, Google Threat Intelligence Group identified a complex espionage campaign attributed to the PRC‑nexus actor UNC6384 that targeted diplomats in Southeast Asia and other global entities. The attackers hijacked web traffic via a captive‑portal and AitM redirect to deliver a digitally signed downloader tracked as STATICPLUGIN, which retrieved a disguised MSI and staged an in‑memory deployment of the SOGU.SEC backdoor (PlugX). The operation abused valid code‑signing certificates, DLL side‑loading via a novel launcher CANONSTAGER, and indirect execution techniques to evade detection. Google issued alerts, added IOCs to Safe Browsing, and recommends enabling Enhanced Safe Browsing, applying updates, and enforcing 2‑Step Verification.

🔔 Unit 42 reports active exploitation of multiple on‑premises SharePoint vulnerabilities collectively dubbed ToolShell, enabling unauthenticated remote code execution, authentication bypass, and path traversal. Activity observed from mid‑July 2025 includes web shell deployment, theft of ASP.NET MachineKeys and ViewState material, and delivery of the 4L4MD4R ransomware in at least one chain. Organizations with internet‑exposed SharePoint servers should assume potential compromise and follow containment, patching, cryptographic rotation, and incident response guidance immediately.