Malicious PDF — malware analysis report

Static analysis result for SHA-256 59164b8849f05254…

MALICIOUS

PDF

79.7 KB Created: 2021-04-15 17:51:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-06-30
MD5: 6f191381713f575bffbe5ac5777f406a SHA-1: 598d56d997102609cd584afb432f11ccfa4f353e SHA-256: 59164b8849f052548e81f3fd622f4fe492ee2ab01c820ad070c514b227bdfd35
186 Risk Score

Malware Insights

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

The PDF file contains a large number of external links, many pointing to disposable domains, which is characteristic of a link farm used for SEO manipulation or to distribute further malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware distribution. The embedded URLs and the nature of the link farm suggest an attempt to lure users to malicious 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://xajibur.ru/strik?utm_term=english+comprehension+passages+with+questions+and+answers+pdf+for+grade+8 PDF link annotation
    • http://nukels.xyz/8418590197932l3c.pdfIn PDF document text
    • http://nakalabaxis.mywebcommunity.org/62654928579.pdfIn PDF document text
    • https://cdn.sqhk.co/fepogosu/hcgewm5/87690361454.pdfIn PDF document text
    • http://helpcreditscore.info/how_to_do_hobbiesyrml8.pdfIn PDF document text
    • https://cdn.sqhk.co/rapedipular/6EXvXhf/27027945937.pdfIn PDF document text
    • https://cdn.sqhk.co/ratijojitud/bjihhyq/kode_with_klossy_logo.pdfIn PDF document text
    • http://limons.space/36695239017j2frc.pdfIn PDF document text
    • https://cdn.sqhk.co/tekixonef/cgeig4u/kavetilekigivemevofajode.pdfIn PDF document text
    • https://cdn.sqhk.co/borefigux/jicjhD5/senya_and_oscar_the_fearless_adventure_mod_apk.pdfIn PDF document text
    • https://xisuludibu.weebly.com/uploads/1/3/5/3/135300694/fudarovuferafof.pdfIn PDF document text
    • https://cdn.sqhk.co/nakijalufiw/hihRUZY/stickman_battle_fight_superhero_stick_fighting_mod_apk.pdfIn PDF document text
    • https://xutafutixon.weebly.com/uploads/1/3/4/5/134576274/9485508.pdfIn PDF document text
    • http://yachts-4-sale.com/72554731564wgpix.pdfIn PDF document text
    • https://zogosozel.weebly.com/uploads/1/3/1/4/131406999/e10a41.pdfIn PDF document text
    • https://lepovomika.weebly.com/uploads/1/3/4/7/134701686/53679fb88fc14.pdfIn PDF document text
    • http://pawezujexas.mywebcommunity.org/lulabomaninova.pdfIn PDF document text
    • https://cdn.sqhk.co/xonivozew/TaDF4AJ/8700993554.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://baletax.onlinewebshop.net/jurag.pdfIn PDF document text
    • https://s3.amazonaws.com/wefadep/indian_express_bitul.pdfIn PDF document text
    • https://s3.amazonaws.com/rubidokezive/faxoregetelajijav.pdfIn PDF document text
    • http://rujidafedisezu.atwebpages.com/mazowejel.pdfIn PDF document text
    • https://s3.amazonaws.com/nuruvapozixix/buvajuvozesaxupakal.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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f807.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF807 5940 bytes
SHA-256: ab4cca6cc9d6eecf594a019b14f81b4647ccf052208f26b880d26a2720c1f40b
font_01_sfnt_off00010c28.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10C28 10732 bytes
SHA-256: 31e817f3c6cacb3d827eab420a130d4dbbee16be14a6966542bd0325ade3343d