Malicious PDF — malware analysis report

Static analysis result for SHA-256 03613e9b27496443…

MALICIOUS

PDF

87.7 KB Created: 2021-05-25 04:31:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-15
MD5: 40108ba7e14536a4409a7d1fb81a5e2d SHA-1: 252cd32947a6c59e2f9dace61d441708f6df3e4e SHA-256: 03613e9b27496443c4afcff54cfc7631653702ea8b6d0f1835d7c50346503237
234 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous external links, many pointing to disposable hosting, suggesting a link farm designed to distribute malware. The presence of a 'password-protected archive' lure and a 'download button' heuristic further indicates a phishing attempt to trick users into downloading a malicious file, likely an application given the 'mod apk droid vpn premium' UTM term. ClamAV also detected this file as Pdf.Phishing.Trojan.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9983

Heuristics 8

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • Password-protected archive handoff high SE_PASSWORD_ARCHIVE_LURE
    Document gives password instructions for an archive or attachment — often used to keep payloads encrypted until after gateway scanning
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://midufefew.ru/strik?utm_term=mod+apk+droid+vpn+premium PDF link annotation
    • https://jomokojexenubi.weebly.com/uploads/1/3/4/8/134877089/2767477.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4421213/normal_5fe1e9d2dbdb8.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4468836/normal_5fdf92ebb65ad.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4467577/normal_601d4ef5cd796.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4455185/normal_603265cece34c.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4453732/normal_604d1dd7b09ba.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4444123/normal_5fd877ec579f9.pdfIn PDF document text
    • https://sidonakitipu.weebly.com/uploads/1/3/4/6/134631457/6453371.pdfIn PDF document text
    • https://tedipoji.weebly.com/uploads/1/3/1/4/131408178/be548a54ed1e.pdfIn PDF document text
    • https://ruregogawumol.weebly.com/uploads/1/3/2/8/132815787/cc5e8c7e8cd17f.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4380876/normal_602108d8b3a15.pdfIn PDF document text
    • https://kekofazejigax.weebly.com/uploads/1/3/4/6/134600595/6176738.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4495241/normal_6002b7aa557b4.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • https://uploads.strikinglycdn.com/files/41182970-b6e9-461b-8754-9f8bf314f304/whats_the_smallest_capital_city_in_the_world.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/da51745e-5466-4be1-a036-655c0d27df19/como_puedo_ser_un_buen_lider_de_jovenes_cristianos.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/cd9f907b-59f2-4297-a830-e66404d7475d/8407717662.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/9f812994-ec34-4e9a-bc0d-e7da7a3c8dec/baby_girl_names_unique_with_meaning.pdfIn PDF document text
    • https://s3.amazonaws.com/zuvovoxigumuz/photoshop_books_for_free_download.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/be848c92-6955-4a73-8821-a938b25e0988/pokemon_x_and_y_emulator_pc_free_download.pdfIn PDF document text
    • https://s3.amazonaws.com/kovilowab/44863502844.pdfIn PDF document text
    • https://s3.amazonaws.com/degisapemifa/pdf_to_word_converter_using_adobe_acrobat.pdfIn PDF document text
    • https://s3.amazonaws.com/jovekus/already_yet_just_exercises.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/5670507e-089e-4fef-ad36-b3e6acfa6485/11876172209.pdfIn PDF document text
    • https://s3.amazonaws.com/baposivarabuj/7370677128.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/5086541c-8afe-4284-a5d0-cfad7828af26/how_to_turn_on_hdmi_on_hitachi_tv.pdfIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://scripts.sil.org/OFLIn PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f58f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF58F 4824 bytes
SHA-256: 491f152b970765b7b023811f460ef058f5018decdd46458be8a532eb19794018
font_01_sfnt_off000105e4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x105E4 11072 bytes
SHA-256: cc28a948724379599fad4831160945aa6f9e7da9ed3ec147dce4c6c8c0b1a44b
font_02_sfnt_off00012bfd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12BFD 16188 bytes
SHA-256: f4b372e8c4da5798052b6d682c24ede3e0ec0f141c74a6947e01270b278a82bc
font_03_sfnt_off0001412c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1412C 4324 bytes
SHA-256: d1f4a20f0e35a0564be54678b929bb8c711862c507f070c2b9a6abea8daf4378