Detectionhightest
Microsoft IIS Connection Strings Decryption
Detects use of aspnet_regiis to decrypt Microsoft IIS connection strings. An attacker with Microsoft IIS web server access via a webshell or alike can decrypt and dump any hardcoded connection strings, such as the MSSQL service account password using aspnet_regiis command.
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Tim Rauch, Elastic SecurityCreated Wed Sep 28Updated Fri Dec 3097dbf6e2-e436-44d8-abee-4261b24d3e41windows
Log Source
WindowsProcess Creation
ProductWindows← raw: windows
CategoryProcess Creation← raw: process_creation
Events generated when a new process is spawned on the system. Covers command-line arguments, parent/child relationships, and process metadata.
Detection Logic
Detection Logic2 selectors
detection:
selection_name:
- Image|endswith: '\aspnet_regiis.exe'
- OriginalFileName: 'aspnet_regiis.exe'
selection_args:
CommandLine|contains|all:
- 'connectionStrings'
- ' -pdf'
condition: all of selection*False Positives
Unknown
False positive likelihood has not been assessed. Additional context may be needed during triage.
References
MITRE ATT&CK
Tactics
Techniques
Rule Metadata
Rule ID
97dbf6e2-e436-44d8-abee-4261b24d3e41
Status
test
Level
high
Type
Detection
Created
Wed Sep 28
Modified
Fri Dec 30
Author
Path
rules/windows/process_creation/proc_creation_win_iis_connection_strings_decryption.yml
Raw Tags
attack.credential-accessattack.t1003