Cross-source coverage

T1539 / ATT&CK

Steal Web Session Cookie

39 rules across 8 sources.

From MITRE ATT&CK 19.2

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.

Platforms
Linux · macOS · Office Suite · SaaS · Windows
Telemetry
WinEventLog:SysmonWinEventLog:Securityauditd:SYSCALLmacos:unifiedlogfs:fsusagem365:unifiedsaas:googleworkspacesaas:okta

How MITRE says to detect it DET0509

Detection of Web Session Cookie Theft via File, Memory, and Network Artifacts

Windows Analytic 1402

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`.

  • WinEventLog:Sysmon EventCode=10
  • WinEventLog:Sysmon EventCode=2
  • WinEventLog:Security EventCode=4688

Linux Analytic 1403

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.

  • auditd:SYSCALL open or read to browser cookie storage
  • auditd:SYSCALL ptrace syscall or access to /proc/*/mem

macOS Analytic 1404

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.

  • macos:unifiedlog vm_read, task_for_pid, or file open to cookie databases
  • fs:fsusage file open for known browser cookie paths

Office Suite Analytic 1405

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.

  • m365:unified RunMacro
  • WinEventLog:Sysmon EventCode=2

SaaS Analytic 1406

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.

  • saas:googleworkspace login with reused session token and mismatched user agent or IP
  • saas:okta session.token.reuse

View on attack.mitre.org ↗

elastic/detection-rules

13 rules
Detection Severity Format
Browser Process Spawned from an Unusual Parent High Elastic TOML
Entra ID Microsoft Authentication Broker Sign-In with Non-Standard User Agent High Elastic TOML
Entra ID Potential AiTM Sign-In via OfficeHome (Tycoon2FA) High Elastic TOML
M365 Potential AiTM UserLoggedIn via Office App (Tycoon2FA) High Elastic TOML
Manual Loading of a Suspicious Chromium Extension High Elastic TOML
Okta AiTM Session Cookie Replay High Elastic TOML
Okta Multiple OS Names Detected for a Single DT Hash High Elastic TOML
Suspicious Web Browser Sensitive File Access High Elastic TOML
AWS IAM User Console Login from Multiple Geolocations Medium Elastic TOML
First Time Python Accessed Sensitive Credential Files Medium Elastic TOML

+ 3 more from elastic/detection-rules → showing the 10 highest-severity

elastic/protections-artifacts

12 rules
Detection Severity Format
Access to Browser Credentials from Suspicious Memory Undefined Elastic TOML
Browser Debugging from Unusual Parent Undefined Elastic TOML
Chrome Browser Spawned from an Unusual Parent Undefined Elastic TOML
Failed Access Attempt to Web Browser Files Undefined Elastic TOML
Failed Attempts to Access Sensitive Files Undefined Elastic TOML
Potential Browser Credentials Stealer Undefined Elastic TOML
Potential Browser Debugging via Localhost Undefined Elastic TOML
Suspicious Access to Web Browser Credential Stores Undefined Elastic TOML
Web Browser Credential Access via Scripting Utility Undefined Elastic TOML
Web Browser Credential Access via Unsigned Process Undefined Elastic TOML

+ 2 more from elastic/protections-artifacts → showing the 10 highest-severity

panther-labs/panther-analysis

4 rules
Detection Severity Format
Okta Login Without Push Critical Panther Python
Potential Compromised Okta Credentials Critical Panther Python
Okta Potentially Stolen Session High Panther Python
AppOmni Alert Passthrough Medium Panther Python

socfortress/Wazuh-Rules

4 rules
Detection Severity Format
Sysmon - Event 1: Process creation · Steal Web Session Cookie (T1539) High Wazuh XML
operation. · office_365.LogonError = InvalidReplyTo Low Wazuh XML
operation. · office_365.LogonError = MissingSigningKeyCertificateNotConfigured Low Wazuh XML
operation. · office_365.LogonError = TriggerBrowserCapabilitiesInterrupt Low Wazuh XML

Azure/Azure-Sentinel

2 rules
Detection Severity Format
Anomalous non-interactive token issuance after interactive sign-in (AiTM pattern) Undefined KQL
Short-window sign-in mismatch between interactive and non-interactive activity Undefined KQL

SigmaHQ/sigma

2 rules
Detection Severity Format
SQLite Chromium Profile Data DB Access High Sigma
SQLite Firefox Profile Data DB Access High Sigma

chronicle/detection-rules

1 rule
Detection Severity Format
okta_suspicious_use_of_a_session_cookie Medium YARA-L

splunk/security_content

1 rule
Detection Severity Format
Okta Suspicious Use of a Session Cookie Undefined SPL

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