Pierluigi Paganini
February 27, 2023
Password management software firm LastPass disclosed a “second attack,” a threat actor used data stolen from the August security breach and combined it with information available from a third-party data breach. Then the attackers exploited a flaw in a third-party media software package to target the firm.
“Our investigation has revealed that the threat actor pivoted from the first incident, which ended on August 12, 2022, but was actively engaged in a new series of reconnaissance, enumeration, and exfiltration activities aligned to the cloud storage environment spanning from August 12, 2022 to October 26, 2022.” reads the update published by the company. “The second incident saw the threat actor quickly make use of information exfiltrated during the first incident, prior to the reset completed by our teams, to enumerate and ultimately exfiltrate data from the cloud storage resources.”
LastPass revealed that the home computer of one of its DevOp engineers was hacked as part of a sophisticated cyberattack.
The attackers targeted one of the four DevOps engineers who had access to the decryption keys needed to access the cloud storage service. The hackers installed a keylogger on the DevOp engineer’s computed and captured his master password.
“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.” continues the update. “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.”
The investigation conducted by the company with the help of the cybersecurity firm Mandiant confirmed the attack on the DevOps engineer’s home computer.
“The threat actor then exported the native corporate vault entries and content of shared folders, which contained encrypted secure notes with access and decryption keys needed to access the AWS S3 LastPass production backups, other cloud-based storage resources, and some related critical database backups.” concludes the update.
In August 2022, the company disclosed a security breach, threat actors had access to portions of the company development environment through a single compromised developer account and stole portions of source code and some proprietary technical information.
In December 2022, LastPass revealed that the data breach suffered in August 2022 may have been more severe than previously thought.
Thursday, the company revealed that threat actors obtained personal information belonging to its customers, including encrypted password vaults.
The company discovered that an unknown threat actor accessed a cloud-based storage environment leveraging information obtained from the August security incident. The attackers used the info accessed to target another employee and obtain credentials and keys which were used to access and decrypt some storage volumes within the cloud-based storage service.
The update highlights that the cloud storage service accessed by the threat actor is physically separate from the production environment.
Once obtained the cloud storage access key and dual storage container decryption keys, the attackers copied information from backup that contained basic customer account information and related metadata. Copied data include company names, end-user names, billing addresses, email addresses, telephone numbers, and the IP addresses from which customers were accessing the LastPass service.
The threat actor also copied a backup of customer vault data from the encrypted storage container which is stored in a proprietary binary format. The backup contains both unencrypted data (i.e. Website URLs) and 256-bit AES-encrypted sensitive (i.e. Website usernames and passwords, secure notes, and form-filled data).
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