Malicious PDF — malware analysis report

Static analysis result for SHA-256 159c8f0b03d8cd1b…

MALICIOUS

PDF

122.7 KB Created: 2021-04-01 12:17:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-22
MD5: 956a16876069c2c0080467c952df16bc SHA-1: 712b9d9c1236eb20a1c9a2b92fa5c8d90298d59a SHA-256: 159c8f0b03d8cd1b7b5d182e41b2b5de6493acb1836bb8c95cf27a48e88e427e
126 Risk Score

Malware Insights

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

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 5

  • 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 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://resalured.ru/strik?utm_term=constitucion+de+puerto+rico+carta+de+derechos PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4391037/normal_604491c24bece.pdfIn PDF document text
    • http://lowufadit.scienceontheweb.net/anexo_4_simples_nacional_2020.pdfIn PDF document text
    • http://polobasopika.mywebcommunity.org/safety_1st_guide_65_sport_expiration_date.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4462046/normal_5fde3f8251458.pdfIn PDF document text
    • http://zuxemesemubozo.mywebcommunity.org/20012850443.pdfIn PDF document text
    • http://fuvesozufinefi.medianewsonline.com/another_love_piano_sheet.pdfIn PDF document text
    • http://xafesuvorolivig.scienceontheweb.net/vegewemewelipirumu.pdfIn PDF document text
    • http://rulabepotinujeb.mypressonline.com/harry_potter_house_quizzes_playbuzz.pdfIn PDF document text
    • http://bidimiw.sportsontheweb.net/tesowudo.pdfIn PDF document text
    • http://wuxixezigitezir.mygamesonline.org/93491101590.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://45f0f727-c607-4398-b3b7-8b42e23b21b2.filesusr.com/ugd/0a84ca_4ff61ce263ff42c0985ad61eb4bdec67.pdf?index=trueIn PDF document text
    • http://tijuvewoduga.onlinewebshop.net/asexual_vs_sexual_reproduction_advantages_and_disadvantages.pdfIn PDF document text
    • https://s3.amazonaws.com/vizegemawokaxe/how_can_i_improve_my_childs_social_skills.pdfIn PDF document text
    • https://s3.amazonaws.com/fuzafuzeruwit/19907766163.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/c92afe80-b12e-474e-9c4f-11d502de6080/when_is_the_new_divergent_coming_out.pdfIn PDF document text
    • https://s3.amazonaws.com/mexesazaxasa/formal_thank_you_letter_for_good_service.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/7623cdf8-9d89-4508-a711-fb2305bc1ee3/23659767993.pdfIn PDF document text
    • https://5548a280-a194-4776-8019-0e256783c1fa.filesusr.com/ugd/f2c1dc_1ddd7d6c4d664cc5a5ad62942b4174d8.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/6c69127a-eb10-45e1-8fdc-b85621dd94c3/52724794317.pdfIn PDF document text
    • http://tediguku.atwebpages.com/aldehyde_ketone_and_carboxylic_acid_questions.pdfIn PDF document text
    • https://11627308-8c8f-4f08-99ed-0ad85160907d.filesusr.com/ugd/682d1c_cac5ace525cb477d8c06ee6a040b9fa1.pdf?index=trueIn PDF document text
    • https://59b17237-83b3-47c6-9d40-f547da5b0434.filesusr.com/ugd/827194_34ef673b2a334c2dae07270b33a96aa8.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/tawovojo/what_is_the_importance_of_clinical_trials.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/414713cb-2470-4bc7-868f-52cf3fea23bb/can_you_adopt_a_kitten_for_free.pdfIn PDF document text
    • https://s3.amazonaws.com/nawosineromigi/shark_navigator_lift-away_deluxe_nv360_upright_vacuum_parts.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_off0001a36a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1A36A 5036 bytes
SHA-256: 23f6308449a0a47c7ac6a584d2f6bf290046aa6ce484be039459ddf5be0c6cf1
font_01_sfnt_off0001b480.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1B480 11764 bytes
SHA-256: 2120e5d4d9b8632eda25b03a007e4d9744b10d60f81311294d7b25ee5104e16b