Malicious PDF — malware analysis report

Static analysis result for SHA-256 79995bbf1b1cfbc4…

MALICIOUS

PDF

75.8 KB Created: 2021-06-10 17:21:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-25
MD5: 9a9a920168f6ec0bd4335cf4ef1939f8 SHA-1: ef3eb01ea04977e617d1877f40fed8d17eaa13e9 SHA-256: 79995bbf1b1cfbc41d7bdfe0684169a50d72d9dfeec4e1a3d581005969e148e8
186 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9995

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://smidgel.ru/pbw?utm_term=ielts+writing+task+2+band+9+samples+pdf PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4424376/normal_5fd2ed6d6d612.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4379732/normal_60504a59583af.pdfIn PDF document text
    • https://lesinagin.weebly.com/uploads/1/3/1/4/131454304/xijixudos_wufudow.pdfIn PDF document text
    • https://rediwikutine.weebly.com/uploads/1/3/4/0/134096605/c906e.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4443329/normal_6033468421ffe.pdfIn PDF document text
    • https://rixemeja.weebly.com/uploads/1/3/4/7/134711448/4334159.pdfIn PDF document text
    • https://kimimidinom.weebly.com/uploads/1/3/1/4/131453749/4694585.pdfIn PDF document text
    • https://zuwuroxiver.weebly.com/uploads/1/3/1/0/131070979/7974097.pdfIn PDF document text
    • https://fopalese.weebly.com/uploads/1/3/5/3/135349797/8233157.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/1b9cb22a-698d-4697-a23b-b352d044004c/how_to_write_a_case_note_uk.pdfIn PDF document text
    • http://kokoxudalux.pbworks.com/f/puppy_for_adoption_near_me.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/a0d81219-2e09-4314-b63e-e2ce5dfe2fcc/fifty_shades_darker_full_hd_movie_download_movies_counter.pdfIn PDF document text
    • http://sejuworepow.pbworks.com/w/file/fetch/144419139/22678260507.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/0294d72d-ce54-4250-b181-a3352a8b4925/zavizofajajosesegozo.pdfIn PDF document text
    • http://fezosubi.pbworks.com/w/file/fetch/144702369/buzuxetefupivut.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/2b54beb9-bfd3-48f0-822d-8f59379e0ef9/80813964719.pdfIn PDF document text
    • http://kiwuwas.pbworks.com/w/file/fetch/144931464/44585788972.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/89e3f4e7-0132-4eb5-9cb7-9cad5be6af5b/what_are_the_dyson_v11_attachments_for.pdfIn PDF document text
    • http://gijorugisaw.pbworks.com/w/file/fetch/144723219/farming_simulator_17_apk_hack_free_download.pdfIn PDF document text
    • http://tufukamapaf.pbworks.com/w/file/fetch/144925650/bizitonozotibafagezu.pdfIn PDF document text
    • http://dadilotofexi.pbworks.com/w/file/fetch/144957777/weridesemi.pdfIn PDF document text
    • http://sowenux.pbworks.com/w/file/fetch/144546228/analyse_the_structure_of_a_text_examples_sentences.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_off0000e928.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE928 5884 bytes
SHA-256: bec58e7280fb6a3a03b69676953a70a7e09260cc1124b8ac4af5cd6bfc1ad39b
font_01_sfnt_off0000fd25.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD25 10592 bytes
SHA-256: 0f0a503c0f32ee32a625a4a90b48e55c0ec138110c83705d408618eefc6e3298