sublimehighRule

Attachment: PDF with link to zip containing a wsf file

Detects a PDF attachment with a link to a ZIP file that contains a WSF file

MITRE ATT&CK

defense-evasion

Detection Query

type.inbound
and any(attachments,
        .file_type == "pdf"
        and any(file.explode(.),
                any(.scan.url.urls,
                    strings.icontains(.url, "zip")
                    and any(ml.link_analysis(.).files_downloaded,
                            any(file.explode(.), .file_extension == "wsf")
                    )
                )
                or any(.scan.url.urls,
                       strings.icontains(.url, "php")
                       and any(ml.link_analysis(.).files_downloaded,
                               any(file.explode(.),
                                   .file_extension == "zip"
                                   and any(.scan.zip.attempted_files,
                                           strings.icontains(., "wsf")
                                   )
                               )
                       )
                )
        )
)

Data Sources

Email MessagesEmail HeadersEmail Attachments

Platforms

References

Tags

Malfam: QakBot

Raw Content

name: "Attachment: PDF with link to zip containing a wsf file"
description: "Detects a PDF attachment with a link to a ZIP file that contains a WSF file"
references:
  - "https://analyzer.sublime.security/?id=596edcf4-507e-4714-8b2d-b1f51c258c70"
  - "https://twitter.com/Cryptolaemus1/status/1649091718552379392"
  - "https://twitter.com/Cryptolaemus1/status/1650826597333696515"
type: "rule"
severity: "high"
source: |
  type.inbound
  and any(attachments,
          .file_type == "pdf"
          and any(file.explode(.),
                  any(.scan.url.urls,
                      strings.icontains(.url, "zip")
                      and any(ml.link_analysis(.).files_downloaded,
                              any(file.explode(.), .file_extension == "wsf")
                      )
                  )
                  or any(.scan.url.urls,
                         strings.icontains(.url, "php")
                         and any(ml.link_analysis(.).files_downloaded,
                                 any(file.explode(.),
                                     .file_extension == "zip"
                                     and any(.scan.zip.attempted_files,
                                             strings.icontains(., "wsf")
                                     )
                                 )
                         )
                  )
          )
  )
tags:
  - "Malfam: QakBot"
attack_types:
  - "Malware/Ransomware"
tactics_and_techniques:
  - "Evasion"
  - "PDF"
detection_methods:
  - "Archive analysis"
  - "Content analysis"
  - "File analysis"
  - "URL analysis"
id: "93bc7db4-248f-502a-bc9a-919915cbc0fb"