T1539: Steal Web Session Cookie
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.
There are several examples of malware targeting cookies from web browsers on the local system. Adversaries may also steal cookies by injecting malicious JavaScript content into websites or relying on User Execution by tricking victims into running malicious JavaScript in their browser.
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) that can be set up by an adversary and used in phishing campaigns.
After an adversary acquires a valid cookie, they can then perform a Web Session Cookie technique to login to the corresponding web application.
How it's found
Detection of Web Session Cookie Theft via File, Memory, and Network Artifacts: Detects suspicious access to browser session cookie storage (e.g., Chrome’s `Cookies` SQLite DB) or memory reads of browser processes. Anomalous injection or memory dump utilities targeting browser processes such as `chrome.exe`, `firefox.exe`, or `msedge.exe`. Detects access to known browser cookie files (e.g., `~/.mozilla/firefox/*.default/cookies.sqlite`, `~/.config/google-chrome/`) and suspicious reads of browser memory via `/proc/[pid]/mem` or ptrace. Detects unauthorized access to browser cookie paths (e.g., `~/Library/Application Support/Google/Chrome/Default/Cookies`) or `task_for_pid`/`vm_read` calls to Safari/Chrome memory space. Detects automation macros or VBA scripts in documents that access browser file paths, read cookie data, or attempt to exfiltrate browser session tokens over HTTP. Detects use of session cookies or authentication tokens from unusual user agents or locations. Identifies token reuse without reauthentication or attempts to bypass MFA using previously stolen cookies.
Standards mapping
Where this fits in a TurboPentest engagement
This weakness is not covered by the automated black-box pentest. IntegSec pentesters cover it in a manual engagement.
Frequently asked questions
What is T1539 Steal Web Session Cookie?
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. There are several examples of malware targeting cookies from web browsers on the local system. Adversaries may also steal cookies by injecting malicious JavaScript content into websites or relying on User Execution by tricking victims into running malicious JavaScript in their browser. 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) that can be set up by an adversary and used in phishing campaigns. After an adversary acquires a valid cookie, they can then perform a Web Session Cookie technique to login to the corresponding web application.
Which tactics does T1539 belong to?
T1539 maps to the Credential Access tactic.
Does TurboPentest test for Steal Web Session Cookie?
This weakness is not covered by the automated black-box pentest. IntegSec pentesters cover it in a manual engagement.
Related MITRE ATT&CK techniques
About this reference
These security references are maintained by IntegSec, an offensive-security firm whose team holds CISSP, OSCP, and OSCE certifications and has run thousands of penetration tests. Content is kept current as tools, standards, and attack techniques evolve.
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