LNK Icon Smuggling
Where this stands
A reviewer read the telemetry and concluded there is nothing here to detect that a sibling technique does not already cover.
AN1134's defining artefact is the IconEnvironmentDataBlock fetch: Explorer resolving a remote icon path for a.LNK produces no process-creation event, and the HTTP/WebDAV retrieval itself is performed by the WebClient service inside svchost.exe, so even the Sysmon EventID 3/22 network leg of the analytic can never be attributed back to the shortcut. No log source in this brief parses.LNK metadata (no field carries the IconEnvironmentDataBlock path), so the sub-technique's own observable is structurally invisible to every log source DET0405 offers. […]
What the technique is
Adversaries may smuggle commands to download malicious payloads past content filters by hiding them within otherwise seemingly benign windows shortcut files. Windows shortcut files (.LNK) include many metadata fields, including an icon location field (also known as the IconEnvironmentDataBlock) designed to specify the path to an icon file that is to be displayed for the LNK file within a host directory. Adversaries may abuse this LNK metadata to download malicious payloads. For example, adversaries have been observed using LNK files as phishing payloads to deliver malware. Once invoked (e.g., Malicious File), payloads referenced via external URLs within the LNK icon location field may be downloaded. These files may also then be invoked by Command and Scripting Interpreter/System Binary Proxy Execution arguments within the target path field of the LNK. LNK Icon Smuggling may also be utilized post compromise, such as malicious scripts executing an LNK on an infected host to download additional malicious payloads.
Read it on attack.mitre.orgWhat MITRE says you would watch
- AN1134
Correlates LNK file execution with embedded resource extraction or suspicious network activity following initial launch, often leading to payload delivery via disguised icons.
Technique names and descriptions © MITRE ATT&CK®, CC BY 4.0. Not endorsed by MITRE.