During the second incident, the threat actor used information obtained during the first one to enumerate and exfiltrate the data stored in the S3 buckets. Monday’s update said that the tactics, techniques, and procedures used in the first incident were different from those used in the second one and that, as a result, it wasn’t initially clear to investigators that the two were directly related.

The new details explain how the threat actor obtained the S3 encryption keys. The backup data contained both unencrypted data, such as website URLs, as well as website usernames and passwords, secure notes, and form-filled data, which had an additional layer of encryption using 256-bit AES. “The threat actor was able to capture the employee’s master password as it was entered, after the employee authenticated with MFA, and gain access to the DevOps engineer’s LastPass corporate vault.” “This was accomplished by targeting the DevOps engineer’s home computer and exploiting a vulnerable third-party media software package, which enabled remote code execution capability and allowed the threat actor to implant keylogger malware,” LastPass officials wrote.

Among other things, the vault gave access to a shared cloud-storage environment that contained the encryption keys for customer vault backups stored in Amazon S3 buckets. In the process, the unknown threat actor was able to steal valid credentials from a senior DevOps engineer and access the contents of a LastPass data vault. Although an initial intrusion into LastPass ended on August 12, officials with the leading password manager said the threat actor “was actively engaged in a new series of reconnaissance, enumeration, and exfiltration activity” from August 12 to August 26.

Plex amazon s3