T1565.002No distinct observable

Transmitted Data Manipulation

ImpactLinux, macOS, Windows

Where this stands

A reviewer read the telemetry and concluded there is nothing here to detect that a sibling technique does not already cover.

The parent T1565 (file write) and T1565.001 (file delete) both hang a rule on a discrete Sysmon file-system event because the manipulation happens at rest. T1565.002 is manipulation in flight, and none of the three per-platform analytics in this brief has a log source that observes content in flight rather than a connection merely existing. Windows AN0702 offers network_connection/dns_query (a socket opened, not what crossed it) and create_stream_hash (a hash taken once, at file creation, with no second reading to diff against -- MITRE's own IntegrityBaseline knob presumes an out-of-band reference this rule has no way to populate). […]

Covered instead by T1565, T1565.001.

What the technique is

Adversaries may alter data en route to storage or other systems in order to manipulate external outcomes or hide activity, thus threatening the integrity of the data. By manipulating transmitted data, adversaries may attempt to affect a business process, organizational understanding, and decision making. Manipulation may be possible over a network connection or between system processes where there is an opportunity deploy a tool that will intercept and change information. The type of modification and the impact it will have depends on the target transmission mechanism as well as the goals and objectives of the adversary. For complex systems, an adversary would likely need special expertise and possibly access to specialized software related to the system that would typically be gained through a prolonged information gathering campaign in order to have the desired impact.

Read it on attack.mitre.org

What MITRE says you would watch

AN0702
Monitor for anomalies in transmitted data streams, including mismatched file integrity checks, API interception, or man-in-the-middle modifications. Detect unexpected use of APIs that handle network I/O where transmitted data integrity could be manipulated.
AN0703
Detect alterations of transmitted data via monitoring syscalls (send, recv, write) or middleware interception. Identify mismatched file hashes when compared at origin vs. destination. Watch for anomalous activity from processes interacting with secure transmission services (e.g., OpenSSL, scp).
AN0704
Monitor system APIs such as CFNetwork and SecureTransport for anomalies in transmitted data streams. Detect mismatches in file hashes or SSL/TLS downgrade attempts that enable manipulation of transmitted data.