Malicious PDF — malware analysis report

Static analysis result for SHA-256 4b55f0dea41313a5…

MALICIOUS

PDF

84.7 KB Created: 2021-02-21 17:32:46 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-22
MD5: 038c0519d9dd3998d84d22ac44822856 SHA-1: 77b9a307939558f378b8bae7d08695fba14b15e8 SHA-256: 4b55f0dea41313a570290085babd1f32fd18001ff5d084ee6bcd1c4dd6264def
186 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many hosted on disposable domains, suggesting a link farm designed to distribute malicious content or phish users. The ClamAV detection and ML classifier strongly indicate malicious intent. Although no scripts were explicitly extracted, the PDF structure and numerous external links point towards a malicious document, likely a spearphishing attachment, that redirects users to potentially harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

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://jacksth.ru/strik?utm_term=how+to+cook+a+precooked+ham+in+a+rival+roaster+oven PDF link annotation
    • https://vevorusafe.weebly.com/uploads/1/3/4/5/134516648/mudebi.pdfIn PDF document text
    • https://cdn.sqhk.co/mugejufunij/3Yhbhin/detective_conan_the_movie_23_wiki.pdfIn PDF document text
    • https://cdn.sqhk.co/tozegatopaxu/dTBibjf/gemabonivagojezebiwe.pdfIn PDF document text
    • https://misamizejip.weebly.com/uploads/1/3/4/3/134348089/jewibepebamowuwa.pdfIn PDF document text
    • https://zodaribidibukez.weebly.com/uploads/1/3/4/7/134716266/f3ee8d.pdfIn PDF document text
    • https://vowevabejera.weebly.com/uploads/1/3/0/7/130775986/pubilokubofulal-wuvomaza.pdfIn PDF document text
    • https://cdn.sqhk.co/jasowipe/wYJhgib/75074119399.pdfIn PDF document text
    • https://cdn.sqhk.co/tuzevawu/hcagfhe/93999698537.pdfIn PDF document text
    • https://cdn.sqhk.co/pajokiman/hFje5jj/76796948591.pdfIn PDF document text
    • https://rofaxebawo.weebly.com/uploads/1/3/4/7/134750080/6512614.pdfIn PDF document text
    • https://cdn.sqhk.co/veleviziwew/PjcGGtp/video_downloader_plus_6._0._2.pdfIn PDF document text
    • https://cdn.sqhk.co/pasepizut/Cn6LifD/amc_24_willowbrook_customer_service_number.pdfIn PDF document text
    • https://tagakokiginozol.weebly.com/uploads/1/3/0/7/130775172/2903254.pdfIn PDF document text
    • https://cdn.sqhk.co/numiwuzuwix/jcijGes/blaze_of_battle_mod_apk_revdl.pdfIn PDF document text
    • https://wazivako.weebly.com/uploads/1/3/0/9/130969042/bijanesew.pdfIn PDF document text
    • https://ponixetuga.weebly.com/uploads/1/3/4/6/134668384/8c472b5f.pdfIn PDF document text
    • https://xazebuwojij.weebly.com/uploads/1/3/4/4/134467588/rataw.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://s3.amazonaws.com/wemupajese/rofabogabuw.pdfIn PDF document text
    • https://s3.amazonaws.com/zerejibixupav/linear_equations_worksheets_grade_8.pdfIn PDF document text
    • https://s3.amazonaws.com/daraniwekamidir/wikoferodugofifivolenud.pdfIn PDF document text
    • https://s3.amazonaws.com/punurum/napubarakosamojuwokide.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_off00010094.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10094 5280 bytes
SHA-256: 62e4a606445f203b12966dbfe852a54a88dee5ca7385b82fe326c2641547d319
font_01_sfnt_off00011268.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11268 10796 bytes
SHA-256: e8a7d09d9e65b9df132618960d12c03b6f4f5b779d2c4f0c119aef60ea0cd5c8
font_02_sfnt_off00013710.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13710 4324 bytes
SHA-256: ff5f0ef16caf3e97cd1984b3a03ea88e11eab8cf63d2ee006085a4b9995833f3