Malicious PDF — malware analysis report

Static analysis result for SHA-256 3903b19b69c3681f…

MALICIOUS

PDF

84.5 KB Created: 2021-06-04 01:47:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-25
MD5: 7612696935747e6c01ecb0af9d48793e SHA-1: 3c1acf7427bb5cd67bdaab509578692a1a7df7c2 SHA-256: 3903b19b69c3681fc9b5675b8c29da82cb7047aae9f5438503d68446ed389be0
186 Risk Score

Malware Insights

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

The PDF file contains a large number of external links, many of which point to disposable hosting services, indicating a link farm designed to drive traffic. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or distributing further malware. The document body, though heavily obfuscated, contains references to 'free spider solitaire app for android' and 'wkhtmltopdf', suggesting a lure to entice users to click on the embedded malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

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://druttle.ru/123?utm_term=free+spider+solitaire+app+for+android PDF link annotation
    • https://tipowunukal.weebly.com/uploads/1/3/4/3/134355136/jipimogetivofu.pdfIn PDF document text
    • https://nimujebiparifil.weebly.com/uploads/1/3/4/7/134730121/rofuwovep.pdfIn PDF document text
    • https://livekurot.weebly.com/uploads/1/3/4/4/134443702/eb0519689c58.pdfIn PDF document text
    • https://xorusisu.weebly.com/uploads/1/3/4/3/134314808/gelawifi-rudelar-ridumozigubizov-sifoliteropive.pdfIn PDF document text
    • https://nizuwutino.weebly.com/uploads/1/3/1/4/131482859/7012599.pdfIn PDF document text
    • https://mazokozofifux.weebly.com/uploads/1/3/4/3/134305155/luwugopovozosumegaj.pdfIn PDF document text
    • https://ponekuxu.weebly.com/uploads/1/3/4/7/134747949/tawodefevuve.pdfIn PDF document text
    • https://bozalugim.weebly.com/uploads/1/3/4/3/134343660/e06e78c6.pdfIn PDF document text
    • https://mujesazuf.weebly.com/uploads/1/3/2/3/132302915/marenagaraze-xukofowero-zunujupir.pdfIn PDF document text
    • https://likuwiwekadu.weebly.com/uploads/1/3/1/8/131857000/dd988ee20ff6a8.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
    • http://sepaxebi.pbworks.com/f/linear_algebra_and_differential_equations_using_matlab.pdfIn PDF document text
    • http://zuvuzut.pbworks.com/f/paano_sinusulat_ang_abstrak_ng_isang_tesis.pdfIn PDF document text
    • http://gitefov.pbworks.com/f/mojaberegaravazevubuzid.pdfIn PDF document text
    • http://vifogajo.pbworks.com/w/file/fetch/144498672/60563230967.pdfIn PDF document text
    • http://kedetuwi.pbworks.com/w/file/fetch/144413232/liwuwutukepobaserovu.pdfIn PDF document text
    • http://wuwolufit.pbworks.com/w/file/fetch/144578124/reasons_why_my_firestick_remote_not_working.pdfIn PDF document text
    • http://gitixofipoxu.pbworks.com/w/file/fetch/144538164/sugubeb.pdfIn PDF document text
    • http://gufabewa.pbworks.com/f/fugijijozunojifed.pdfIn PDF document text
    • http://tarogifere.pbworks.com/w/file/fetch/144520908/23098533555.pdfIn PDF document text
    • http://xojifot.pbworks.com/w/file/fetch/144425820/81247938612.pdfIn PDF document text
    • http://gufabewa.pbworks.com/w/file/fetch/144578055/bourjois_healthy_mix_serum_foundation_shade_finder.pdfIn PDF document text
    • http://lomexalipele.pbworks.com/f/gta_online_where_to_find_molotovs.pdfIn PDF document text
    • http://xetuduju.pbworks.com/w/file/fetch/144536490/who_is_the_strongest_norse_god.pdfIn PDF document text
    • http://garewewaziwu.pbworks.com/f/49198593188.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0001010c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1010C 4776 bytes
SHA-256: 11afff754141ad9b417473b39435c244a02c589faddea295be011f91a88237bf
font_01_sfnt_off0001114f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1114F 10936 bytes
SHA-256: e7d3d8f6d96141186d8388e31f41036b66eb4e29b81984a08025b056ef411271
font_02_sfnt_off00013655.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13655 4324 bytes
SHA-256: ff5f0ef16caf3e97cd1984b3a03ea88e11eab8cf63d2ee006085a4b9995833f3