Exploit Public-Facing Application

Agrius exploits public-facing applications for initial access to victim environments. Examples include widespread attempts to exploit CVE-2018-13379 in FortiOS devices and SQL injection activity.^[10]

APT28 has used a variety of public exploits, including CVE 2020-0688 and CVE 2020-17144, to gain execution on vulnerable Microsoft Exchange; they have also conducted SQL injection attacks against external websites.^[11][12]

APT29 has exploited CVE-2019-19781 for Citrix, CVE-2019-11510 for Pulse Secure VPNs, CVE-2018-13379 for FortiGate VPNs, and CVE-2019-9670 in Zimbra software to gain access.^[13][14]

APT39 has used SQL injection for initial compromise.^[15]

APT41 exploited CVE-2020-10189 against Zoho ManageEngine Desktop Central through unsafe deserialization, and CVE-2019-19781 to compromise Citrix Application Delivery Controllers (ADC) and gateway devices.^[16] APT41 leveraged vulnerabilities such as ProxyLogon exploitation or SQL injection for initial access.^[17] APT41 exploited CVE-2021-26855 against a vulnerable Microsoft Exchange Server to gain initial access to the victim network.^[18]

APT5 has exploited vulnerabilities in externally facing software and devices including Pulse Secure VPNs and Citrix Application Delivery Controllers.^{[19][20][21] [22]}

Axiom has been observed using SQL injection to gain access to systems.^[23][24]

BackdoorDiplomacy has exploited CVE-2020-5902, an F5 BIP-IP vulnerability, to drop a Linux backdoor. BackdoorDiplomacy has also exploited mis-configured Plesk servers.^[25]

BlackTech has exploited a buffer overflow vulnerability in Microsoft Internet Information Services (IIS) 6.0, CVE-2017-7269, in order to establish a new HTTP or command and control (C2) server.^[26]

Blue Mockingbird has gained initial access by exploiting CVE-2019-18935, a vulnerability within Telerik UI for ASP.NET AJAX.^[27]

During C0017, APT41 exploited CVE-2021-44207 in the USAHerds application and CVE-2021-44228 in Log4j, as well as other .NET deserialization, SQL injection, and directory traversal vulnerabilities to gain initial access.^[28]

During C0018, the threat actors exploited VMWare Horizon Unified Access Gateways that were vulnerable to several Log4Shell vulnerabilities, including CVE-2021-44228, CVE-2021-45046, CVE-2021-45105, and CVE-2021-44832.^[29]

During C0027, Scattered Spider exploited CVE-2021-35464 in the ForgeRock Open Access Management (OpenAM) application server to gain initial access.^[30]

Cinnamon Tempest has exploited multiple unpatched vulnerabilities for initial access including vulnerabilities in Microsoft Exchange, Manage Engine AdSelfService Plus, Confluence, and Log4j.^{[31][32][33][34]}

COATHANGER is installed following exploitation of a vulnerable FortiGate device. ^[35]

During Cutting Edge, threat actors exploited CVE-2023-46805 and CVE-2024-21887 in Ivanti Connect Secure VPN appliances to enable authentication bypass and command injection. A server-side request forgery (SSRF) vulnerability, CVE-2024-21893, was identified later and used to bypass mitigations for the initial two vulnerabilities by chaining with CVE-2024-21887.^{[36][37][38][39][40]}

Dragonfly has conducted SQL injection attacks, exploited vulnerabilities CVE-2019-19781 and CVE-2020-0688 for Citrix and MS Exchange, and CVE-2018-13379 for Fortinet VPNs.^[41]

Earth Lusca has compromised victims by directly exploiting vulnerabilities of public-facing servers, including those associated with Microsoft Exchange and Oracle GlassFish.^[42]

Ember Bear gains initial access to victim environments by exploiting external-facing services. Examples include exploitation of CVE-2021-26084 in Confluence servers; CVE-2022-41040, ProxyShell, and other vulnerabilities in Microsoft Exchange; and multiple vulnerabilities in open-source platforms such as content management systems.^[43][44]

FIN13 has exploited known vulnerabilities such as CVE-2017-1000486 (Primefaces Application Expression Language Injection), CVE-2015-7450 (WebSphere Application Server SOAP Deserialization Exploit), CVE-2010-5326 (SAP NewWeaver Invoker Servlet Exploit), and EDB-ID-24963 (SAP NetWeaver ConfigServlet Remote Code Execution) to gain initial access.^[45][46]

FIN7 has compromised targeted organizations through exploitation of CVE-2021-31207 in Exchange.^[31]

Fox Kitten has exploited known vulnerabilities in Fortinet, PulseSecure, and Palo Alto VPN appliances.^{[47][48][49][50][51]}

GALLIUM exploited a publicly-facing servers including Wildfly/JBoss servers to gain access to the network.^[52][53]

GOLD SOUTHFIELD has exploited Oracle WebLogic vulnerabilities for initial compromise.^[54]

HAFNIUM has exploited CVE-2021-44228 in Log4j and CVE-2021-26855, CVE-2021-26857, CVE-2021-26858, and CVE-2021-27065 to compromise on-premises versions of Microsoft Exchange Server.^{[55][56][57][58][32]}

Havij is used to automate SQL injection.^[59]

For HomeLand Justice, threat actors exploited CVE-2019-0604 in Microsoft SharePoint for initial access.^[60]

INC Ransom has exploited known vulnerabilities including CVE-2023-3519 in Citrix NetScaler for initial access.^[61][62]

Ke3chang has compromised networks by exploiting Internet-facing applications, including vulnerable Microsoft Exchange and SharePoint servers.^[63]

Kimsuky has exploited various vulnerabilities for initial access, including Microsoft Exchange vulnerability CVE-2020-0688.^[64]

Magic Hound has exploited the Log4j utility (CVE-2021-44228), on-premises MS Exchange servers via "ProxyShell" (CVE-2021-34473, CVE-2021-34523, CVE-2021-31207), and Fortios SSL VPNs (CVE-2018-13379).^{[65][66][67][68][69][32]}

menuPass has leveraged vulnerabilities in Pulse Secure VPNs to hijack sessions.^[70]

Moses Staff has exploited known vulnerabilities in public-facing infrastructure such as Microsoft Exchange Servers.^[71]

MuddyWater has exploited the Microsoft Exchange memory corruption vulnerability (CVE-2020-0688).^[72]

During Night Dragon, threat actors used SQL injection exploits against extranet web servers to gain access.^[73]

During Operation CuckooBees, the threat actors exploited multiple vulnerabilities in externally facing servers.^[74]

During Operation Wocao, threat actors gained initial access by exploiting vulnerabilities in JBoss webservers.^[75]

Play has exploited known vulnerabilities for initial access including CVE-2018-13379 and CVE-2020-12812 in FortiOS and CVE-2022-41082 and CVE-2022-41040 ("ProxyNotShell") in Microsoft Exchange.^[76][77]

Rocke exploited Apache Struts, Oracle WebLogic (CVE-2017-10271), and Adobe ColdFusion (CVE-2017-3066) vulnerabilities to deliver malware.^[78][79]

Sandworm Team exploits public-facing applications for initial access and to acquire infrastructure, such as exploitation of the EXIM mail transfer agent in Linux systems.^[80][81]

Siloscape is executed after the attacker gains initial access to a Windows container using a known vulnerability.^[82]

During the SolarWinds Compromise, APT29 exploited CVE-2020-0688 against the Microsoft Exchange Control Panel to regain access to a network.^[83][13]

SoreFang can gain access by exploiting a Sangfor SSL VPN vulnerability that allows for the placement and delivery of malicious update binaries.^[84]

sqlmap can be used to automate exploitation of SQL injection vulnerabilities.^[85]

Threat Group-3390 has exploited the Microsoft SharePoint vulnerability CVE-2019-0604 and CVE-2021-26855, CVE-2021-26857, CVE-2021-26858, and CVE-2021-27065 in Exchange Server.^[86]

ToddyCat has exploited the ProxyLogon vulnerability (CVE-2021-26855) to compromise Exchange Servers at multiple organizations.^[87]

Versa Director Zero Day Exploitation involved exploitation of a vulnerability in Versa Director servers, since identified as CVE-2024-39717, for initial access and code execution.^[88]

Volatile Cedar has targeted publicly facing web servers, with both automatic and manual vulnerability discovery.^{[89] [90]}

Volt Typhoon has gained initial access through exploitation of multiple vulnerabilities in internet-facing software and appliances such as Fortinet, Ivanti (formerly Pulse Secure), NETGEAR, Citrix, and Cisco.^[91][92]

Winter Vivern has exploited known and zero-day vulnerabilities in software usch as Roundcube Webmail servers and the "Follina" vulnerability.^[93][94]

ZxShell has been dropped through exploitation of CVE-2011-2462, CVE-2013-3163, and CVE-2014-0322.^[95]

Application isolation will limit what other processes and system features the exploited target can access.

Web Application Firewalls may be used to limit exposure of applications to prevent exploit traffic from reaching the application.

Segment externally facing servers and services from the rest of the network with a DMZ or on separate hosting infrastructure.

Use least privilege for service accounts will limit what permissions the exploited process gets on the rest of the system.

Update software regularly by employing patch management for externally exposed applications.

Regularly scan externally facing systems for vulnerabilities and establish procedures to rapidly patch systems when critical vulnerabilities are discovered through scanning and through public disclosure.^[8]