has used spearphishing emails with malicious attachments to initially compromise victims.(Citation: Proofpoint TA505 Sep 2017)(Citation: Proofpoint TA505 June 2018)(Citation: Proofpoint TA505 Jan 2019)(Citation: Cybereason TA505 April 2019)(Citation: ProofPoint SettingContent-ms July 2018)(Citation: Proofpoint TA505 Mar 2018)(Citation: Trend Micro TA505 June 2019)(Citation: Proofpoint TA505 October 2019)
Below is an instruction that describes a task, paired with an input that provides further context. Write a response that appropriately completes the request. ### Instruction: List the MITRE techniques contained in the text. ### Input: has used spearphishing emails with malicious attachments to initially compromise victims.(Citation: Proofpoint TA505 Sep 2017)(Citation: Proofpoint TA505 June 2018)(Citation: Proofpoint TA505 Jan 2019)(Citation: Cybereason TA505 April 2019)(Citation: ProofPoint SettingContent-ms July 2018)(Citation: Proofpoint TA505 Mar 2018)(Citation: Trend Micro TA505 June 2019)(Citation: Proofpoint TA505 October 2019) ### Response: T1566.001.