T1486 Data Encrypted for Impact

Technique: T1486
Tactics: Impact
Research, 90 days: 1
KEV CVEs mapped: 15
SigmaHQ rules: 16
Elastic, Splunk: 26
thrunt rules: 0
Upstream: https://attack.mitre.org/techniques/T1486

MITRE description

Adversaries may encrypt data on target systems or on large numbers of systems in a network to interrupt availability to system and network resources. They can attempt to render stored data inaccessible by encrypting files or data on local and remote drives and withholding access to a decryption key. This may be done in order to extract monetary compensation from a victim in exchange for decryption or a decryption key (ransomware) or to render data permanently inaccessible in cases where the key is not saved or transmitted.(Citation: US-CERT Ransomware 2016)(Citation: FireEye WannaCry 2017)(Citation: US-CERT NotPetya 2017)(Citation: US-CERT SamSam 2018) In the case of ransomware, it is typical that common user files like Office documents, PDFs, images, videos, audio, text, and source code files will be encrypted (and often renamed and/or tagged with specific file markers). Adversaries may need to first employ other behaviors, such as [File and Directory Permissions Modification](https://attack.mitre.org/techniques/T1222) or [System Shutdown/Reboot](https://attack.mitre.org/techniques/T1529), in order to unlock and/or gain access to manipulate these files.(Citation: CarbonBlack Conti July 2020) In some cases, adversaries may encrypt critical system files, disk partitions, and the MBR.(Citation: US-CERT NotPetya 2017) Adversaries may also encrypt virtual machines hosted on ESXi or other hypervisors.(Citation: Crowdstrike Hypervisor Jackpotting Pt 2 2021) To maximize impact on the target organization, malware designed for encrypting data may have worm-like features to propagate across a network by leveraging other attack techniques like [Valid Accounts](https://attack.mitre.org/techniques/T1078), [OS Credential Dumping](https://attack.mitre.org/techniques/T1003), and [SMB/Windows Admin Shares](https://attack.mitre.org/techniques/T1021/002).(Citation: FireEye WannaCry 2017)(Citation: US-CERT NotPetya 2017) Encryption malware may also leverage [Internal Defacement](https://attack.mitre.org/techniques/T1491/001), such as changing victim wallpapers or ESXi server login messages, or otherwise intimidate victims by sending ransom notes or other messages to connected printers (known as "print bombing").(Citation: NHS Digital Egregor Nov 2020)(Citation: Varonis) In cloud environments, storage objects within compromised accounts may also be encrypted.(Citation: Rhino S3 Ransomware Part 1) For example, in AWS environments, adversaries may leverage services such as AWS’s Server-Side Encryption with Customer Provided Keys (SSE-C) to encrypt data.(Citation: Halcyon AWS Ransomware 2025)

KEV CVEs mapped to this technique

MITRE CTID maps these KEV CVEs to this technique by hand. They are the actively exploited vulnerabilities behind this technique's KEV signal.

Research citing this technique

Reports and advisories from the last 90 days that cite this technique.

2026-10-29 Cisco Talos: IR trends Q3 2026: Actors impersonate IT help desks in vishing attacks as ransomware activity increases

Detection coverage

SigmaHQ community rules

WannaCry Ransomware Activity (emerging-threats)
LockerGoga Ransomware Activity (emerging-threats)
Potential Conti Ransomware Activity (emerging-threats)
BlueSky Ransomware Artefacts (emerging-threats)
FunkLocker Ransomware File Creation (emerging-threats)
Suspicious Creation TXT File in User Desktop (threat-hunting)
Antivirus - Ransomware Signature (core)
AWS EC2 Disable EBS Encryption (core)
AWS KMS Imported Key Material Usage (core)
Microsoft 365 - Potential Ransomware Activity (core)
Suspicious Appended Extension (core)
Load Of RstrtMgr.DLL By A Suspicious Process (core)
Load Of RstrtMgr.DLL By An Uncommon Process (core)
Portable Gpg.EXE Execution (core)
Suspicious Reg Add BitLocker (core)
Renamed Gpg.EXE Execution (core)

Elastic and Splunk rules

Potential AWS S3 Bucket Ransomware Note Uploaded (elastic)
Excessive AWS S3 Object Encryption with SSE-C (elastic)
AWS S3 Object Encryption Using External KMS Key (elastic)
Unusual AWS S3 Object Encryption with SSE-C (elastic)
Ransomware - Detected - Elastic Defend (elastic)
Ransomware - Prevented - Elastic Defend (elastic)
Deprecated - M365 Security Compliance Potential Ransomware Activity (elastic)
ESXi Payload Executed Against Datastore (elastic)
Suspicious Renaming of ESXI Files (elastic)
Suspicious Data Encryption via OpenSSL Utility (elastic)
Potential Linux Ransomware Note Creation Detected (elastic)
Potential NFS Destructive Operation Burst (elastic)
PowerShell Script with Encryption/Decryption Capabilities (elastic)
Potential Ransomware Behavior - Note Files by System (elastic)
Suspicious File Renamed via SMB (elastic)
Potential Ransomware Note File Dropped via SMB (elastic)
ASL AWS Detect Users creating keys with encrypt policy without MFA (splunk)
AWS Detect Users creating keys with encrypt policy without MFA (splunk)
AWS Detect Users with KMS keys performing encryption S3 (splunk)
High Process Termination Frequency (splunk)
Ransomware Notes bulk creation (splunk)
Ryuk Test Files Detected (splunk)
Samsam Test File Write (splunk)
Windows .Key File Creation in Root Directory (splunk)
Windows BitLocker Suspicious Command Usage (splunk)

Showing 25 of 26.

Signal counts reflect the current corpus snapshot. Research citations are the technique IDs named in vendor reports and government advisories from the last 90 days; KEV mappings come from MITRE CTID. Coverage is the SigmaHQ rule inventory (core, emerging-threats, threat-hunting) at release r2026-07-01 plus Elastic and Splunk production rules. Rule bodies are not mirrored; links go upstream.