Query: EDR alert: possible Steal Web Session Cookie (T1539)
Matching passage: T1539 Steal Web Session Cookie. Tactics: credential access. Description: An adversary may steal web application or service session cookies and use them to gain access to web applications or Internet services as an authenticated user without needing credentials. Web applications and services often use session cookies as an authentication token after a user has authenticated to a website. Cookies are often valid for an extended period of time, even if the web application is not actively used. Cookies can be found on disk, in the process memory of the browser, and in network traffic to remote systems. Additionally, other applications on the targets machine might store sensitive authentication cookies in memory (e.g. apps which authenticate to cloud services). Session cookies can be used to bypasses some multi-factor authentication protocols.(Citation: Pass The Cookie) There are several examples of malware targeting cookies from web browsers on the local system.(Citation: Kaspersky TajMahal April 2019)(Citation: Unit 42 Mac Crypto Cookies January 2019) Adversaries may also steal cookies by injecting malicious JavaScript content into websites or relying on [User Execution](https://attack.mitre.org/techniques/T1204) by tricking victims into running malicious JavaScript in their browser.(Citation: Talos Roblox Scam 2023)(Citation: Krebs Discord Bookmarks 2023) There are also open source frameworks such as `Evilginx2` and `Muraena` that can gather session cookies through a malicious proxy (e.g., [Adversary-in-the-Middle](https://attack.mitre.org/techniques/T1557)) that can be set up by an adversary and used in phishing campaigns.(Citation: Github evilginx2)(Citation: GitHub Mauraena) After an adversary acquires a valid cookie, they can then perform a [Web Session Cookie](https://attack.mitre.org/techniques/T1550/004) technique to login to the corresponding web application.
Near-miss passage: T1556.007 Hybrid Identity. Tactics: defense impairment, persistence, credential access. Description: Adversaries may patch, modify, or otherwise backdoor cloud authentication processes that are tied to on-premises user identities in order to bypass typical authentication mechanisms, access credentials, and enable persistent access to accounts. Many organizations maintain hybrid user and device identities that are shared between on-premises and cloud-based environments. These can be maintained in a number of ways. For example, Microsoft Entra ID includes three options for synchronizing identities between Active Directory and Entra ID(Citation: Azure AD Hybrid Identity): * Password Hash Synchronization (PHS), in which a privileged on-premises account synchronizes user password hashes between Active Directory and Entra ID, allowing authentication to Entra ID to take place entirely in the cloud * Pass Through Authentication (PTA), in which Entra ID authentication attempts are forwarded to an on-premises PTA agent, which validates the credentials against Active Directory * Active Directory Federation Services (AD FS), in which a trust relationship is established between Active Directory and Entra ID AD FS can also be used with other SaaS and cloud platforms such as AWS and GCP, which will hand off the authentication process to AD FS and receive a token containing the hybrid users’ identity and privileges. By modifying authentication processes tied to hybrid identities, an adversary may be able to establish persistent privileged access to cloud resources. For example, adversaries who compromise an on-premises server running a PTA agent may inject a malicious DLL into the `AzureADConnectAuthenticationAgentService` process that authorizes all attempts to authenticate to Entra ID, as well as records user credentials.(Citation: Azure AD Connect for Read Teamers)(Citation: AADInternals Azure AD On-Prem to Cloud) In environments using AD FS, an adversary may edit the `Microsoft.IdentityServer.Servicehost` configuration file to load a malicious DLL that generates authentication