Adversaries may delete or remove built-in data and turn off services designed to aid in the recovery of a corrupted system to prevent recovery.(Citation: Talos Olympic Destroyer 2018)(Citation: FireEye WannaCry 2017) This may deny access to available backups and recovery options.
Operating systems may contain features that can help fix corrupted systems, such as a backup catalog, volume shadow copies, and automatic repair features. Adversaries may disable or delete system recovery features to augment the effects of Data Destruction and Data Encrypted for Impact.(Citation: Talos Olympic Destroyer 2018)(Citation: FireEye WannaCry 2017) Furthermore, adversaries may disable recovery notifications, then corrupt backups.(Citation: disable_notif_synology_ransom)
A number of native Windows utilities have been used by adversaries to disable or delete system recovery features:
On network devices, adversaries may leverage Disk Wipe to delete backup firmware images and reformat the file system, then System Shutdown/Reboot to reload the device. Together this activity may leave network devices completely inoperable and inhibit recovery operations.
Adversaries may also delete “online” backups that are connected to their network – whether via network storage media or through folders that sync to cloud services.(Citation: ZDNet Ransomware Backups 2020) In cloud environments, adversaries may disable versioning and backup policies and delete snapshots, machine images, and prior versions of objects designed to be used in disaster recovery scenarios.(Citation: Dark Reading Code Spaces Cyber Attack)(Citation: Rhino Security Labs AWS S3 Ransomware)
View in MITRE ATT&CK®| Capability ID | Capability Description | Mapping Type | ATT&CK ID | ATT&CK Name | Notes |
|---|---|---|---|---|---|
| CVE-2023-36884 | Microsoft Windows Search Remote Code Execution Vulnerability | secondary_impact | T1490 | Inhibit System Recovery |
Comments
This remote code execution vulnerability in Microsoft Office has been exploited by adversarial groups to distribute ransomware. Attackers use specially crafted Microsoft Office documents to bypass security features, enabling remote code execution without user prompts. These documents are typically delivered through phishing techniques, enticing victims to open them. Once opened, the ransomware encrypts files and demands a ransom for decryption, while also removing system backups and leaving a ransom note threatening data loss if recovery is attempted without the provided decryptor key.
The ransomware further erases system logs and may publish stolen data on leak websites, leading to unauthorized access to sensitive information and potential installation of backdoors for further exploitation. Microsoft addressed this vulnerability in their security updates by introducing measures to make file paths unpredictable, thereby mitigating the exploit chain. Despite these updates, additional vulnerabilities in Microsoft Office and Windows were identified. Security solutions offer protection against these exploits, and findings are shared with cybersecurity alliances to enhance collective defense efforts.
This vulnerability has been exploited by the Russian group Storm-0978, also known as RomCom, who craft specially designed Microsoft Office documents related to the Ukrainian World Congress. These documents bypass Microsoft's Mark-of-the-Web (MotW) security feature, enabling remote code execution without security prompts. The adversary used phishing techniques to deliver these documents, enticing victims to open them. Once opened, the ransomware, known as Underground, executes, encrypting files and demanding a ransom for decryption.
The ransomware further removes shadow copies, terminates MS SQL Server services, and leaves a ransom note threatening data loss if recovery is attempted without their decryptor key. It also erases Windows Event logs and publishes stolen victim data on a data leak website, causing unauthorized access to sensitive information and potential installation of backdoors for further exploitation.
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