Exploit Public-Facing Application

Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network. The weakness in the system can be a software bug, a temporary glitch, or a misconfiguration.

Exploited applications are often websites/web servers, but can also include databases (like SQL), standard services (like SMB or SSH), network device administration and management protocols (like SNMP and Smart Install), and any other system with Internet accessible open sockets.[1][2][3][4][5] Depending on the flaw being exploited this may also involve Exploitation for Defense Evasion or Exploitation for Client Execution.

If an application is hosted on cloud-based infrastructure and/or is containerized, then exploiting it may lead to compromise of the underlying instance or container. This can allow an adversary a path to access the cloud or container APIs, exploit container host access via Escape to Host, or take advantage of weak identity and access management policies.

Adversaries may also exploit edge network infrastructure and related appliances, specifically targeting devices that do not support robust host-based defenses.[6][7]

For websites and databases, the OWASP top 10 and CWE top 25 highlight the most common web-based vulnerabilities.[8][9]

ID: T1190
Sub-techniques:  No sub-techniques
Tactic: Initial Access
Platforms: Containers, IaaS, Linux, Network, Windows, macOS
Contributors: Praetorian; Yossi Weizman, Azure Defender Research Team
Version: 2.5
Created: 18 April 2018
Last Modified: 28 November 2023

Procedure Examples

ID Name Description
G0007 APT28

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.[10][11]

G0016 APT29

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.[12][13]

G0087 APT39

APT39 has used SQL injection for initial compromise.[14]

G0096 APT41

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.[15] APT41 leveraged vulnerabilities such as ProxyLogon exploitation or SQL injection for initial access.[16]

G1023 APT5

APT5 has exploited vulnerabilities in externally facing software and devices including Pulse Secure VPNs and Citrix Application Delivery Controllers.[17][18][19] [20]

G0001 Axiom

Axiom has been observed using SQL injection to gain access to systems.[21][22]

G0135 BackdoorDiplomacy

BackdoorDiplomacy has exploited CVE-2020-5902, an F5 BIP-IP vulnerability, to drop a Linux backdoor. BackdoorDiplomacy has also exploited mis-configured Plesk servers.[23]

G0098 BlackTech

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.[24]

G0108 Blue Mockingbird

Blue Mockingbird has gained initial access by exploiting CVE-2019-18935, a vulnerability within Telerik UI for ASP.NET AJAX.[25]

C0017 C0017

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.[26]

C0018 C0018

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.[27]

C0027 C0027

During C0027, Scattered Spider exploited CVE-2021-35464 in the ForgeRock Open Access Management (OpenAM) application server to gain initial access.[28]

G1021 Cinnamon Tempest

Cinnamon Tempest has exploited multiple unpatched vulnerabilities for initial access including vulnerabilities in Microsoft Exchange, Manage Engine AdSelfService Plus, Confluence, and Log4j.[29][30][31][32]


COATHANGER is installed following exploitation of a vulnerable FortiGate device. [33]

C0029 Cutting Edge

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.[34][35][36][37][38]

G0035 Dragonfly

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.[39]

G1006 Earth Lusca

Earth Lusca has compromised victims by directly exploiting vulnerabilities of public-facing servers, including those associated with Microsoft Exchange and Oracle GlassFish.[40]

G1016 FIN13

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.[41][42]

G0046 FIN7

FIN7 has compromised targeted organizations through exploitation of CVE-2021-31207 in Exchange.[29]

G0117 Fox Kitten

Fox Kitten has exploited known vulnerabilities in Fortinet, PulseSecure, and Palo Alto VPN appliances.[43][44][45][46][47]


GALLIUM exploited a publicly-facing servers including Wildfly/JBoss servers to gain access to the network.[48][49]


GOLD SOUTHFIELD has exploited Oracle WebLogic vulnerabilities for initial compromise.[50]


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.[51][52][53][54][30]

S0224 Havij

Havij is used to automate SQL injection.[55]

G0004 Ke3chang

Ke3chang has compromised networks by exploiting Internet-facing applications, including vulnerable Microsoft Exchange and SharePoint servers.[56]

G0094 Kimsuky

Kimsuky has exploited various vulnerabilities for initial access, including Microsoft Exchange vulnerability CVE-2020-0688.[57]

G0059 Magic Hound

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).[58][59][60][61][62][30]

G0045 menuPass

menuPass has leveraged vulnerabilities in Pulse Secure VPNs to hijack sessions.[63]

G1009 Moses Staff

Moses Staff has exploited known vulnerabilities in public-facing infrastructure such as Microsoft Exchange Servers.[64]

G0069 MuddyWater

MuddyWater has exploited the Microsoft Exchange memory corruption vulnerability (CVE-2020-0688).[65]

C0002 Night Dragon

During Night Dragon, threat actors used SQL injection exploits against extranet web servers to gain access.[66]

C0012 Operation CuckooBees

During Operation CuckooBees, the threat actors exploited multiple vulnerabilities in externally facing servers.[67]

C0014 Operation Wocao

During Operation Wocao, threat actors gained initial access by exploiting vulnerabilities in JBoss webservers.[68]

G0106 Rocke

Rocke exploited Apache Struts, Oracle WebLogic (CVE-2017-10271), and Adobe ColdFusion (CVE-2017-3066) vulnerabilities to deliver malware.[69][70]

G0034 Sandworm Team

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.[71][72]

S0623 Siloscape

Siloscape is executed after the attacker gains initial access to a Windows container using a known vulnerability.[73]

C0024 SolarWinds Compromise

During the SolarWinds Compromise, APT29 exploited CVE-2020-0688 against the Microsoft Exchange Control Panel to regain access to a network.[74][12]

S0516 SoreFang

SoreFang can gain access by exploiting a Sangfor SSL VPN vulnerability that allows for the placement and delivery of malicious update binaries.[75]

S0225 sqlmap

sqlmap can be used to automate exploitation of SQL injection vulnerabilities.[76]

G0027 Threat Group-3390

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.[77]

G1022 ToddyCat

ToddyCat has exploited the ProxyLogon vulnerability (CVE-2021-26855) to compromise Exchange Servers at multiple organizations.[78]

G0123 Volatile Cedar

Volatile Cedar has targeted publicly facing web servers, with both automatic and manual vulnerability discovery.[79] [80]

G1017 Volt Typhoon

Volt Typhoon gained initial access through exploitation of CVE-2021-40539 in internet-facing ManageEngine ADSelfService Plus servers.[81]

S0412 ZxShell

ZxShell has been dropped through exploitation of CVE-2011-2462, CVE-2013-3163, and CVE-2014-0322.[82]


ID Mitigation Description
M1048 Application Isolation and Sandboxing

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

M1050 Exploit Protection

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

M1030 Network Segmentation

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

M1026 Privileged Account Management

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

M1051 Update Software

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

M1016 Vulnerability Scanning

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]


ID Data Source Data Component Detects
DS0015 Application Log Application Log Content

Detecting software exploitation may be difficult depending on the tools available. Software exploits may not always succeed or may cause the exploited process to become unstable or crash. Web Application Firewalls may detect improper inputs attempting exploitation.

DS0029 Network Traffic Network Traffic Content

Use deep packet inspection to look for artifacts of common exploit traffic, such as SQL injection strings or known payloads. For example, monitor for successively chained functions that adversaries commonly abuse (i.e. gadget chaining) through unsafe deserialization to exploit publicly facing applications for initial access.[83]


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