Keylogging
Where this stands
No Sigma rule can address this — the telemetry MITRE names has no Sigma logsource behind it.
Sigma has no logsource taxonomy for mobile platforms. MITRE's telemetry here is mobile EDR and device APIs, which no Sigma rule can address.
What the technique is
Adversaries may log user keystrokes to intercept credentials or other information from the user as the user types them. Some methods of keylogging include: Masquerading as a legitimate third-party keyboard to record user keystrokes. On both Android and iOS, users must explicitly authorize the use of third-party keyboard apps. Users should be advised to use extreme caution before granting this authorization when it is requested. Abusing accessibility features. On Android, adversaries may abuse accessibility features to record keystrokes by registering an AccessibilityService class, overriding the onAccessibilityEvent method, and listening for the AccessibilityEvent.TYPE_VIEW_TEXT_CHANGED event type. The event object passed into the function will contain the data that the user typed. *Additional methods of keylogging may be possible if root access is available.
Read it on attack.mitre.orgWhat MITRE says you would watch
- AN1751
Defender correlates an app acquiring input-capture capability (AccessibilityService enablement or default IME set) with high-frequency text-change/IME commit callbacks sourced from other packages, followed by local keylog persistence and/or small, immediate network egress. Chain: capability/permission → intercept (accessibility ‘TYPE_VIEW_TEXT_CHANGED’ or IME commitText/onStartInput bursts) → persist to container → near-term egress.
- AN1752
Defender correlates a custom keyboard extension activation (optionally with TCC ‘Full Access’) or abnormal UI text-entry interception with local keylog persistence and/or small egress. Chain: capability/consent (keyboard Full Access/TCC) → intercept (keyboard commit events or repeated secure text entry edits) → persist to container → near-term egress.
Technique names and descriptions © MITRE ATT&CK®, CC BY 4.0. Not endorsed by MITRE.