Malicious PDF — malware analysis report

Static analysis result for SHA-256 844d5f8a5e86f4cf…

MALICIOUS

PDF

76.6 KB Created: 2021-03-16 22:09:51 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-22
MD5: a5305089eec95a48704b2480fdbd4d80 SHA-1: 99c13f3f41a89fb55b7a96eca1231310c74d5a2f SHA-256: 844d5f8a5e86f4cfffeafae77576eb23dc8377a786341ebd4d315611fac9bad4
186 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF file contains numerous external links, many pointing to disposable domains, suggesting a link farm or SEO spam operation. The ClamAV detection and ML classifier strongly indicate malicious intent, likely related to phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and link farm behavior are indicative of malicious document techniques.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.
  • 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.
  • 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://soxebez.ru/123?utm_term=bjcp+tasting+exam+scoresheet PDF link annotation
    • https://fagugirawax.weebly.com/uploads/1/3/4/3/134388021/tezapote.pdfIn PDF document text
    • http://wodekenizowa.getenjoyment.net/becoming_familiar_with_lab_equipment_worksheet_answer_key.pdfIn PDF document text
    • https://cdn.sqhk.co/pekotegafod/i3jabhb/furafogasevimajivil.pdfIn PDF document text
    • https://cdn.sqhk.co/mugapowejog/cidjjGJ/fufidutofi.pdfIn PDF document text
    • https://boxusopusaw.weebly.com/uploads/1/3/1/3/131398197/8938121.pdfIn PDF document text
    • https://cdn.sqhk.co/puwipaneke/cichcig/vesibepipuduzakinalemerad.pdfIn PDF document text
    • http://rufoferapavinew.medianewsonline.com/ncaa_division_2_basketball_championship_2019.pdfIn PDF document text
    • https://lexabebuwapo.weebly.com/uploads/1/3/1/3/131383838/f80a765ae58364.pdfIn PDF document text
    • https://cdn.sqhk.co/gizetinediz/iebCHmc/videos_for_whatsapp_status_app.pdfIn PDF document text
    • https://xadularapiro.weebly.com/uploads/1/3/1/4/131437383/lafadoji-fadobugamagum-dovazufamijarix-vujabupiv.pdfIn PDF document text
    • http://lirinevewafa.mypressonline.com/19866064070.pdfIn PDF document text
    • https://nukanepinax.weebly.com/uploads/1/3/1/4/131454046/fenurebunuxasizibis.pdfIn PDF document text
    • http://bagomebefekixob.getenjoyment.net/vojigikezinezurodopisod.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://uploads.strikinglycdn.com/files/99e8c220-78f1-4fa2-86fa-a4d3dc8e0676/minn_kota_i_pilot_vs_i_pilot_link.pdfIn PDF document text
    • https://s3.amazonaws.com/zalisujezajaje/23498766003.pdfIn PDF document text
    • https://s3.amazonaws.com/wetevali/gangster_game_app_android.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/0618fb77-495d-44f2-9818-bc7a016659de/how_to_set_up_coway_air_purifier.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/c9d3ab35-6a64-4a39-80a8-ba83c4236359/wildgame_innovations_xb370_crossbow_package.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/9cf9dd04-cb06-4c8e-b5b2-337fd8db31ca/bugesagemejakoninutasati.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/a45371fe-a334-44cc-8727-8d133c406aa0/harriet_tubman_biography_book.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/9ce85828-2541-434b-b3df-4ab2607ae316/74745155916.pdfIn PDF document text
    • http://nojikigor.myartsonline.com/fisoduzidavojijudu.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/1a08d253-e9df-4b85-aad8-120031535d99/81953000998.pdfIn PDF document text
    • https://s3.amazonaws.com/wopari/android_game_development_course_hyderabad.pdfIn PDF document text
    • https://s3.amazonaws.com/wizuluworafid/22938979813.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

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ed3a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED3A 5508 bytes
SHA-256: 6302339eab63d0ef36b28791a4d33aa0883b975c8d7321fa3874660898c7fef0
font_01_sfnt_off0000ffd7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFFD7 10888 bytes
SHA-256: aaf90131fea0e4c122f1be8e3a508979d07204322dfb9398946a61bd5966da84