Malicious PDF — malware analysis report

Static analysis result for SHA-256 85f21daefa241573…

MALICIOUS

PDF

80.2 KB Created: 2021-03-25 01:35:03 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-23
MD5: e83c5003ceb3d3b24657c117f91ed18b SHA-1: be2719d5a1611482ecf2adfc9df5148c40d4737e SHA-256: 85f21daefa24157322fc2f04491e5679256631492d9b31a571cf4fba859c210f
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 0.9991

Heuristics 6

  • 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.
  • 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://zajinet.ru/award?keyword=adoption+forms+south+africa+pdf PDF link annotation
    • http://websecurer.tech/wufokatulusaba0zza.pdfIn PDF document text
    • http://alcexpress3.xyz/basic_vba_excel_tutorialspzf0.pdfIn PDF document text
    • https://xekexudaxojow.weebly.com/uploads/1/3/4/3/134365032/majiropavatixugeja.pdfIn PDF document text
    • https://cdn.sqhk.co/javufikari/5ghI3ji/1671682127.pdfIn PDF document text
    • https://bimevaxufozuz.weebly.com/uploads/1/3/2/6/132683359/4973aefbae.pdfIn PDF document text
    • https://siwusoxol.weebly.com/uploads/1/3/4/5/134584737/c7c4e978d9d.pdfIn PDF document text
    • http://thedefenseforge.com/childhood_immunization_schedule_2018_philippinescz8su.pdfIn PDF document text
    • http://characduwe.space/kamasutra_book_in_english_onlinecu55k.pdfIn PDF document text
    • http://bestita.space/butterball_deep_fried_turkey_breast_walmartb399b.pdfIn PDF document text
    • http://theraisins.pro/dafiwezuzowolobiwimoloymf2x.pdfIn PDF document text
    • http://vigastlens.xyz/what_are_the_abbreviations_for_cooking_measurements1ydjw.pdfIn PDF document text
    • http://aires.fun/samsung_nu7100_price_in_nepal5dmp4.pdfIn PDF document text
    • https://cdn.sqhk.co/fimirexuf/dFjhifS/salofewemaseboteka.pdfIn PDF document text
    • https://cdn.sqhk.co/dedogupazib/hjcwwgc/dinoren.pdfIn PDF document text
    • http://russianpatentexpert.com/graphing_quadratic_equations_worksheets9x7pk.pdfIn PDF document text
    • https://zumuwezejulo.weebly.com/uploads/1/3/1/4/131455722/fuzugaberiwe-zufulo-wazinugep-zunefazoparoje.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://e5eb5b25-b33c-43e3-82d5-57ab1bf863d8.filesusr.com/ugd/b0c717_36685dc2c4444415a159bdd739724653.pdf?index=trueIn PDF document text
    • https://662517ce-f374-4037-aebd-99b1dbe00103.filesusr.com/ugd/0c4177_185c36ae1f4f452287bce739a21947b4.pdf?index=trueIn PDF document text
    • https://6129906d-bc82-46a7-99f5-71793a58af3c.filesusr.com/ugd/d162e3_226b4c9b25b5495cbf0fb3f8ef30d009.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/1004bf43-ede4-480d-bb78-1480888e75c2/55223266685.pdfIn PDF document text
    • https://580b68e3-2104-4118-ae5b-4f285de1c062.filesusr.com/ugd/dad7b5_a275b4032df344d2a48b3be709fca443.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/d9558d4b-2462-4b9a-9930-dd82bc27cf6a/82480648509.pdfIn PDF document text
    • https://36622f5a-5a1b-41a5-aa98-965156e47ac2.filesusr.com/ugd/804ff6_83c4dbcc37d64449be68f19f4f6e50a0.pdf?index=trueIn 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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e89a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE89A 5116 bytes
SHA-256: 5e9cca54d4da7d71c898e0b58b61b3254a4f45c61eb4d58918b7daf0797f4690
font_01_sfnt_off0000f9c8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF9C8 13108 bytes
SHA-256: 455492c0dc4f45e00069e63cff2fa7e524d53110abbd8e2e2781ec6dcf795e8f
font_02_sfnt_off00012384.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12384 4324 bytes
SHA-256: a542ec26cea93e049a2e27cd59b1347dd9bbdea13775fd7b822b3c2b3136116f