Sigma rule: Registry Modification for OCI DLL Redirection

Rule

Title

Registry Modification for OCI DLL Redirection

Status

experimental

Level

high

Author

Swachchhanda Shrawan Poudel (Nextron Systems)

Date

2026-01-24

File

rules/windows/registry/registry_set/registry_set_potential_oci_dll_redirection.yml

Commit

ccbb0369507f796db0b0ae6854c8a2be471b9d84

Detects registry modifications related to 'OracleOciLib' and 'OracleOciLibPath' under 'MSDTC' settings.
Threat actors may modify these registry keys to redirect the loading of 'oci.dll' to a malicious DLL, facilitating phantom DLL hijacking via the MSDTC service.

Log source

product

windows

category

registry_set

Detection

selection_ocilib:
    TargetObject|endswith: '\SOFTWARE\Microsoft\MSDTC\MTxOCI\OracleOciLib'
filter_main_ocilib_file:
    # it is looking when oci.dll name is changed to something else like evil.dll
    Details|contains: 'oci.dll'
selection_ocilibpath:
    TargetObject|endswith: '\SOFTWARE\Microsoft\MSDTC\MTxOCI\OracleOciLibPath'
filter_main_ocilibpath:
    # it is looking when oci.dll path is changed to something else like 'C:\Windows\Temp\'
    Details|contains: '%SystemRoot%\System32\'
condition: (selection_ocilib and not filter_main_ocilib_file) or (selection_ocilibpath and not filter_main_ocilibpath)

False positives (as the rule lists them)

• Unlikely

Tags

• attack.persistence
• attack.privilege-escalation
• attack.execution
• attack.stealth
• attack.defense-impairment
• attack.t1112
• attack.t1574.001

MITRE ATT&CK ids this rule names

• T1112
• T1574.001

References

• https://www.crowdstrike.com/en-us/blog/4-ways-adversaries-hijack-dlls/

Read on 2026-11-03T00:58:21.399Z under licence sigma-drl-1.1@d5f4c36a from https://github.com/SigmaHQ/sigma/blob/ccbb0369507f796db0b0ae6854c8a2be471b9d84/rules/windows/registry/registry_set/registry_set_potential_oci_dll_redirection.yml