Malicious PDF — malware analysis report

Static analysis result for SHA-256 916d4cd0225d696d…

MALICIOUS

PDF

81.9 KB Created: 2021-09-17 07:26:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: e729b140db077bd458a0e35a00932786 SHA-1: 53d3e3abeb955c2dc0de28d9c2668b57a9648726 SHA-256: 916d4cd0225d696d5540ffc8819767f82c8d2230d5f2f38bc27d3f096394a3d7
126 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many pointing to disposable hosting and exhibiting link farm characteristics, strongly suggesting a phishing or malware distribution scheme. The ML classifier and ClamAV detection confirm its malicious nature. The sample's primary function appears to be redirecting users to potentially harmful external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 5

  • 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://cructi.ru/uplcv?utm_term=escape+master+apk PDF link annotation
    • https://porfic.com/fotos/file/26426816673.pdfIn PDF document text
    • https://vhssirimpanam.org/ckfinder/userfiles/files/zenopatuzukawedelorobuxuz.pdfIn PDF document text
    • https://larustt.com/upload/ckfinder/files/bizozi.pdfIn PDF document text
    • http://22vek-omsk.ru/fck_editor_files/files/poleximixalebivixuwa.pdfIn PDF document text
    • http://massiimo.com/piceditor/file/79931166520.pdfIn PDF document text
    • http://safetruck.gr/images/file/lepigako.pdfIn PDF document text
    • http://architettotoma.it/userfiles/files/difup.pdfIn PDF document text
    • https://anglarill.net/userfiles/file/loziditasuvebex.pdfIn PDF document text
    • http://www.lovebliss.tw/UserFiles/files/23236693772.pdfIn PDF document text
    • https://giyimkent.formenemlak.com/upload/ckfinder/files/77286553099.pdfIn PDF document text
    • http://leeclinic.kr/userData/board/file/77800058355.pdfIn PDF document text
    • http://halongbaycruises.org/upload/files/nebiviwuw.pdfIn PDF document text
    • http://kondicionery-noginsk.ru/upload_picture/file/wutogewam.pdfIn PDF document text
    • http://eskuvotoszkanaban.hu/editor_up/nedimopufoga.pdfIn PDF document text
    • http://neza.cz/UserFiles/File/68591356866.pdfIn PDF document text
    • http://krajinar.cz/soubory/files/3241411556.pdfIn PDF document text
    • https://www.temsilcisitesi.com/wp-content/plugins/formcraft/file-upload/server/content/files/16132eefe27323---jinujiberituregida.pdfIn PDF document text
    • https://listapp.in/ci/userfiles/files/niwiziwukunewodavije.pdfIn PDF document text
    • https://noble-worldwide.com/wp-content/plugins/super-forms/uploads/php/files/613390e2204c255d6549f07c6e9e1f42/kamolalapojanuxivip.pdfIn PDF document text
    • https://www.confirmedtour.com/files/41603883787.pdfIn PDF document text
    • http://tuvanluatdanang.com/upload/ck/files/94951405563.pdfIn PDF document text
    • http://smartpaintingplus.com/userfiles/files/koxifajidolu.pdfIn PDF document text
    • http://adhunikjewellers.com/ckfinder/userfiles/files/98364918243.pdfIn PDF document text
    • http://annabarons.com/files/files/86468984702.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://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d814.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD814 10248 bytes
SHA-256: 19ac092e9cc72b13f6557fc80cededef88d6a71998f3e9f81dc67992471d057e
font_01_sfnt_off0000ef2c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF2C 19392 bytes
SHA-256: 067aab7e2c7a07932cbf47ea5fb4dc30bbb598ffece0bb87cfcb9244a1a6642d
font_02_sfnt_off000121ea.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x121EA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1