Malicious PDF — malware analysis report

Static analysis result for SHA-256 166079f344ac1293…

MALICIOUS

PDF

76.0 KB Created: 2021-03-19 21:12:43 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: b886ec84432f20762d191136570402b2 SHA-1: 104c687b9921897d1acb78245bfd91c474b9a304 SHA-256: 166079f344ac129302f6db839f47afb02740a2f66f71d2e25a3eda8184c5bcc9
186 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF document contains a large number of external links, indicating it functions as a link farm. Several heuristics, including PDF_SEO_LINK_FARM and PDF_SEO_DISPOSABLE_LINK_FARM, confirm this behavior. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution through the linked sites. No scripts were extracted, and the document body was unreadable.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

Heuristics 6

  • 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.
  • 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://jacksth.ru/award?keyword=alfa+laval+pump+handbook+pdf
    • https://mezovojexojija.weebly.com/uploads/1/3/0/8/130874002/3604834.pdf
    • https://zijobukevas.weebly.com/uploads/1/3/1/4/131454580/tekavelesarakimizok.pdf
    • https://cdn.sqhk.co/xaripisi/hjshbj6/35348519506.pdf
    • http://wepisoja.mypressonline.com/10821536655.pdf
    • https://vekosafadowob.weebly.com/uploads/1/3/4/8/134868088/54d702d4.pdf
    • http://xoxuvajes.mywebcommunity.org/amplificador_pioneer_class_d_monoblock.pdf
    • http://powajaxib.medianewsonline.com/defiant_digital_timer_3_way_installation.pdf
    • https://cdn.sqhk.co/vapumojemov/cgiVhfW/wolateda.pdf
    • https://cdn.sqhk.co/gizivapejoko/hibPhcF/pagekupefuj.pdf
    • https://medivurufif.weebly.com/uploads/1/3/1/4/131407406/joxuja-sopusikiwegedo-binaz-fawanupusuxewip.pdf
    • https://cdn.sqhk.co/nanubebebot/S6Phcja/data_structures_and_algorithms_using_python.pdf
    • https://cdn.sqhk.co/kewesowovim/Yiiheja/70515511733.pdf
    • http://sidufapas.mywebcommunity.org/realidades_2_capitulo_3a_answers_page_49.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • http://www.daltonmaag.com/
    • https://662517ce-f374-4037-aebd-99b1dbe00103.filesusr.com/ugd/0c4177_54a9174e9c9647359ff64201c0156dea.pdf?index=true
    • https://6205d428-d5dc-494e-bbc3-e2236f9d811e.filesusr.com/ugd/6885a6_e51bde510ad9437a83aa53fa9b0702c6.pdf?index=true
    • https://5d3a3edc-1384-4eb0-a354-174dd54c13aa.filesusr.com/ugd/7f5dc5_364e4c90e88244b08968981367d650f9.pdf?index=true
    • http://ziwemasux.myartsonline.com/modal_verbs_worksheets_for_grade_6_with_answers.pdf
    • https://41fe7446-7195-45c8-906d-de5e784989f9.filesusr.com/ugd/e02969_0e49efcd96e64405a847435259d2f6df.pdf?index=true
    • https://bd7a0a6f-bbfd-49cc-ba41-c3f2778102d9.filesusr.com/ugd/9ea91e_8a89b2d331ae46afa361e2124f0571ff.pdf?index=true
    • http://wutorokanotomav.onlinewebshop.net/59573055186.pdf
    • http://koriwironawuva.myartsonline.com/alphanumeric_symbol_series_questions.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://scripts.sil.org/OFL

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d0fc.bin
d5dac7ba55695bc3b3142b665f710a7dd660195dfc5e21c3195472a2be025dba
pdf-font-stream PDF embedded font (sfnt) at offset 0xD0FC 4504 bytes
font_01_sfnt_off0000e0e0.bin
9aa7c3818e277373a2ffe4bcf557bd725a42ebf44aafa1dd82bcbc52103c25b6
pdf-font-stream PDF embedded font (sfnt) at offset 0xE0E0 4896 bytes
font_02_sfnt_off0000f154.bin
b796fbc7eaa8dbc82fcead26d14f9937f9764ccdb128b13b7bab170fa7ff843a
pdf-font-stream PDF embedded font (sfnt) at offset 0xF154 10288 bytes
font_03_sfnt_off0001146b.bin
ff5f0ef16caf3e97cd1984b3a03ea88e11eab8cf63d2ee006085a4b9995833f3
pdf-font-stream PDF embedded font (sfnt) at offset 0x1146B 4324 bytes