Detection rules › Sigma

Potential DLL Sideloading Of Libcurl.DLL Via GUP.EXE

Status
test
Severity
medium
Log source
product windows, category image_load
Author
Nasreddine Bencherchali (Nextron Systems)
Source
github.com/SigmaHQ/sigma

Detects potential DLL sideloading of "libcurl.dll" by the "gup.exe" process from an uncommon location

MITRE ATT&CK coverage

Event coverage

ProviderEventTitle
SysmonEvent ID 7Image loaded

Rule body yaml

title: Potential DLL Sideloading Of Libcurl.DLL Via GUP.EXE
id: e49b5745-1064-4ac1-9a2e-f687bc2dd37e
status: test
description: Detects potential DLL sideloading of "libcurl.dll" by the "gup.exe" process from an uncommon location
references:
    - https://labs.withsecure.com/publications/fin7-target-veeam-servers
author: Nasreddine Bencherchali (Nextron Systems)
date: 2023-05-05
tags:
    - attack.persistence
    - attack.privilege-escalation
    - attack.execution
    - attack.stealth
    - attack.t1574.001
logsource:
    category: image_load
    product: windows
detection:
    selection:
        Image|endswith: '\gup.exe'
        ImageLoaded|endswith: '\libcurl.dll'
    filter_main_notepad_plusplus:
        Image|endswith: '\Notepad++\updater\GUP.exe'
    condition: selection and not 1 of filter_main_*
falsepositives:
    - Unknown
level: medium

Stages and Predicates

Stage 0: condition

selection and not 1 of filter_main_*

Stage 1: selection

selection:
    Image|endswith: '\gup.exe'
    ImageLoaded|endswith: '\libcurl.dll'

Stage 2: not filter_main_notepad_plusplus

filter_main_notepad_plusplus:
    Image|endswith: '\Notepad++\updater\GUP.exe'

Exclusions

Top-level NOT(...) conjuncts: predicates this rule actively suppresses.

FieldKindExcluded values
Imageends_with\Notepad++\updater\GUP.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
Imageends_with
  • \gup.exe corpus 5 (sigma 5)
ImageLoadedends_with
  • \libcurl.dll