T1550.004 Web Session Cookie
Sub-technique of: T1550
High-Level Description
Adversaries can use stolen session cookies to authenticate to web applications and services. This technique bypasses some multi-factor authentication protocols since the session is already authenticated.
Authentication cookies are commonly used in web applications, including cloud-based services, after a user has authenticated to the service so credentials are not passed and re-authentication does not need to occur as frequently. Cookies are often valid for an extended period of time, even if the web application is not actively used. After the cookie is obtained through Steal Web Session Cookie or Web Cookies, the adversary may then import the cookie into a browser they control and is then able to use the site or application as the user for as long as the session cookie is active. Once logged into the site, an adversary can access sensitive information, read email, or perform actions that the victim account has permissions to perform.
There have been examples of malware targeting session cookies to bypass multi-factor authentication systems.
Kill Chain Phase
- Defense Evasion (TA0005)
- Lateral Movement (TA0008)
Platforms: SaaS, IaaS, Office Suite
What to Check
- Identify if Web Session Cookie technique is applicable to target environment
- Check SaaS systems for indicators of Web Session Cookie
- Check IaaS systems for indicators of Web Session Cookie
- Check Office Suite systems for indicators of Web Session Cookie
- Verify mitigations are bypassed or absent (1 known mitigations)
- Assess detection coverage (1 detection strategies)
How to Test
Manual Testing
Identify Attack Surface: Determine if the target environment is susceptible to Web Session Cookie by examining the target platforms (SaaS, IaaS, Office Suite).
Assess Existing Defenses: Review whether mitigations for T1550.004 are in place. If defenses are absent or misconfigured, this technique may be exploitable.
Execute Test: Use tools and methods described in the MITRE ATT&CK page and external references below.
Note: No Atomic Red Team tests available for this technique. See Atomic Red Team GitHub for updates.
Remediation Guide
M1054 Software Configuration
Configure browsers or tasks to regularly delete persistent cookies.
Detection
Detect Use of Stolen Web Session Cookies Across Platforms
Risk Assessment
| Finding | Severity | Impact |
|---|---|---|
| Web Session Cookie technique applicable | High | Defense Evasion |
CWE Categories
| CWE ID | Title |
|---|---|
| CWE-693 | Protection Mechanism Failure |