Detection rules › Sigma

Exploit for CVE-2017-0261

Status
test
Severity
medium
Log source
product windows, category process_creation
Author
Florian Roth (Nextron Systems)
Source
github.com/SigmaHQ/sigma

Detects Winword starting uncommon sub process FLTLDR.exe as used in exploits for CVE-2017-0261 and CVE-2017-0262

MITRE ATT&CK coverage

Event coverage

Rule body yaml

title: Exploit for CVE-2017-0261
id: 864403a1-36c9-40a2-a982-4c9a45f7d833
status: test
description: Detects Winword starting uncommon sub process FLTLDR.exe as used in exploits for CVE-2017-0261 and CVE-2017-0262
references:
    - https://www.fireeye.com/blog/threat-research/2017/05/eps-processing-zero-days.html
author: Florian Roth (Nextron Systems)
date: 2018-02-22
modified: 2021-11-27
tags:
    - attack.execution
    - attack.t1203
    - attack.t1204.002
    - attack.initial-access
    - attack.t1566.001
    - cve.2017-0261
    - detection.emerging-threats
logsource:
    category: process_creation
    product: windows
detection:
    selection:
        ParentImage|endswith: '\WINWORD.EXE'
        Image|contains: '\FLTLDR.exe'
    condition: selection
falsepositives:
    - Several false positives identified, check for suspicious file names or locations (e.g. Temp folders)
level: medium

Stages and Predicates

Stage 0: condition

selection

Stage 1: selection

selection:
    ParentImage|endswith: '\WINWORD.EXE'
    Image|contains: '\FLTLDR.exe'

Indicators

Each row is a field, operator, and value that the rule matches. The corpus column counts how many other rules in the catalog look for the same combination: high numbers point to widely-used, community-vetted indicators. Blank or 1 shows that the indicator is specific to this rule.

FieldKindValues
Imagematch
  • \FLTLDR.exe
ParentImageends_with
  • \WINWORD.EXE corpus 10 (sigma 10)