IMPORTANT: No additional bug fixes or documentation updates
will be released for this version. For the latest information, see the
current release documentation.
Adobe Hijack Persistence
editAdobe Hijack Persistence
editDetects writing executable files that will be automatically launched by Adobe Acrobat Reader on launch.
Rule type: eql
Rule indices:
- winlogbeat-*
- logs-endpoint.events.*
- logs-windows.*
Severity: low
Risk score: 21
Runs every: 5m
Searches indices from: now-9m (Date Math format, see also Additional look-back time
)
Maximum alerts per execution: 100
References:
Tags:
- Elastic
- Host
- Windows
- Threat Detection
- Persistence
Version: 10
Rule authors:
- Elastic
Rule license: Elastic License v2
Investigation guide
edit## Triage and analysis ### Investigating Adobe Hijack Persistence Attackers can replace the `RdrCEF.exe` executable with their own to maintain their access, which will be launched whenever Adobe Acrobat Reader is executed. #### Possible investigation steps - Investigate the process execution chain (parent process tree). - Identify the user account that performed the action. - Investigate other alerts associated with the user/host during the past 48 hours. - Check for similar behavior in other hosts on the environment. - Retrieve the file and determine if it is malicious: - Use a private sandboxed malware analysis system to perform analysis. - Observe and collect information about the following activities: - Attempts to contact external domains and addresses. - File and registry access, modification, and creation activities. - Service creation and launch activities. - Scheduled tasks creation. - Use the PowerShell Get-FileHash cmdlet to get the SHA-256 hash value of the file. - Search for the existence and reputation of this file in resources like VirusTotal, Hybrid-Analysis, CISCO Talos, Any.run, etc. ### False positive analysis - This activity is unlikely to happen legitimately. Benign true positives (B-TPs) can be added as exceptions if necessary. ### Response and remediation - Initiate the incident response process based on the outcome of the triage. - Isolate the involved host to prevent further post-compromise behavior. - If the triage identified malware, search the environment for additional compromised hosts. - Implement any temporary network rules, procedures, and segmentation required to contain the malware. - Immediately block the IoCs identified. - Remove and block malicious artifacts identified on the triage. - Disable the involved accounts, or restrict their ability to log on remotely. - Reset passwords for the user account and other potentially compromised accounts (email, services, CRMs, etc.). ## Config If enabling an EQL rule on a non-elastic-agent index (such as beats) for versions <8.2, events will not define `event.ingested` and default fallback for EQL rules was not added until 8.2, so you will need to add a custom pipeline to populate `event.ingested` to @timestamp for this rule to work.
Rule query
editfile where event.type == "creation" and file.path : ("?:\\Program Files (x86)\\Adobe\\Acrobat Reader DC\\Reader\\AcroCEF\\RdrCEF.exe", "?:\\Program Files\\Adobe\\Acrobat Reader DC\\Reader\\AcroCEF\\RdrCEF.exe") and not process.name : "msiexec.exe"
Framework: MITRE ATT&CKTM
-
Tactic:
- Name: Persistence
- ID: TA0003
- Reference URL: https://attack.mitre.org/tactics/TA0003/
-
Technique:
- Name: Hijack Execution Flow
- ID: T1574
- Reference URL: https://attack.mitre.org/techniques/T1574/
-
Sub-technique:
- Name: Services File Permissions Weakness
- ID: T1574.010
- Reference URL: https://attack.mitre.org/techniques/T1574/010/