Malicious PDF — malware analysis report

Static analysis result for SHA-256 20ef071f9a717f55…

MALICIOUS

PDF

69.8 KB Created: 2021-03-31 18:43:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-24
MD5: e1f84f13f8b7879650d185220b8dfd11 SHA-1: b3aecf1fc8298983ca7edefb422cc0cba8d9f76e SHA-256: 20ef071f9a717f553991558b6da684257ad1ca1628a82d509dec2d16f0c1f39f
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 0.9996

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://kuzutuzo.ru/strik?utm_term=diagrama+de+fase+binario+explicaci%25C3%25B3n PDF link annotation
    • https://cdn.sqhk.co/pudamunipum/jhiahdj/internet_explorer_7_for_android.pdfIn PDF document text
    • https://gejizataki.weebly.com/uploads/1/3/3/9/133997606/4071022.pdfIn PDF document text
    • https://sujarusokebukok.weebly.com/uploads/1/3/1/4/131437349/kelevobiralik_pububuf.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4367624/normal_5febf1f0533a8.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4490269/normal_606006e6708c7.pdfIn PDF document text
    • https://cdn.sqhk.co/fekepazerox/hfk3oic/bialik_college_school_uniform.pdfIn PDF document text
    • https://pikoxujedogusu.weebly.com/uploads/1/3/4/6/134665618/rinibuvutujetobo.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4404727/normal_601ec4f56542f.pdfIn PDF document text
    • https://mejekuveko.weebly.com/uploads/1/3/5/3/135392268/kamubuvosa.pdfIn PDF document text
    • https://dojifidixiwaji.weebly.com/uploads/1/3/4/3/134372722/jutuxo.pdfIn PDF document text
    • https://janewabogub.weebly.com/uploads/1/3/4/4/134483822/delimijigudupa.pdfIn PDF document text
    • https://sepuzudagek.weebly.com/uploads/1/3/5/3/135329554/niwavenivepito_rufozexux.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4477400/normal_5fe2a8b46c37d.pdfIn PDF document text
    • https://mimitokiwunas.weebly.com/uploads/1/3/4/0/134012498/namumexa-raruwenuvome.pdfIn PDF document text
    • https://bilurowunolip.weebly.com/uploads/1/3/4/3/134316979/balodamosako.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://uploads.strikinglycdn.com/files/531688e4-1b7a-4ba5-bf93-d3dcab674f65/37553039514.pdfIn PDF document text
    • https://4d75d3c9-3a4d-4df6-84ab-e48b83d723e5.filesusr.com/ugd/cdb50c_3d606894098c486b895d4ce3e77df3ce.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/6b445975-1afc-4ed8-be01-ee2c60df83dc/13_signos_del_teatro_ilustrados.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/b9555f10-5f9a-4d24-8691-c32222f493bd/53479266848.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/4a68472a-32eb-4003-b050-990aa0d4456c/fexigovumibabixati.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/0a4eddcd-eba1-46b8-8c30-4d92b59f731f/wozuwupiton.pdfIn PDF document text
    • https://c301b42c-deab-4116-afcd-a09dd0728425.filesusr.com/ugd/4bb894_366c8257c01a4de0a7f9550ce291a628.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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ce3d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCE3D 5816 bytes
SHA-256: 18976fcc4938ca240acb35cba1508ad0160fb4e75fa2e5d5ca1add4fc290d186
font_01_sfnt_off0000e1bc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE1BC 11492 bytes
SHA-256: 26db778260f06385bbf25c9257de9a5c1f594bee3e6208a9638eb226be6362e9