Malicious PDF — malware analysis report

Static analysis result for SHA-256 44ff91ea087168aa…

MALICIOUS

PDF

83.3 KB Created: 2021-09-17 22:16:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: ec29a379a24038e24e0e3aa6619c2bf8 SHA-1: 367759fe6ca81c9c01557914424e0ce1326a5588 SHA-256: 44ff91ea087168aa5a0bddef2dccc8d6bfe1e164c049713b298449916d0c338a
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external URIs pointing to disposable hosting, a strong indicator of a link farm used for phishing or malware distribution. The ML classifier and ClamAV detection further support its malicious nature. Although no scripts were explicitly extracted, the PDF structure and embedded links suggest an attempt to redirect the user to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9912

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://queure.ru/uplcv?utm_term=how+to+reset+android+battery PDF link annotation
    • http://thesciencenetwork.org/uploads/files/25743473088.pdfIn PDF document text
    • http://botosani.ro/img/uploads/file/94163403500.pdfIn PDF document text
    • https://zibarajabi.com/cache/fck_files/file/gitubawenigesubebebuvego.pdfIn PDF document text
    • https://pgp-puh.hr/fck_media/file/2692782786.pdfIn PDF document text
    • http://boek.se/bilder_umeny/File/57954665008.pdfIn PDF document text
    • http://www.norestim.ro/wp-content/plugins/formcraft/file-upload/server/content/files/161403d9409d78---mowavesa.pdfIn PDF document text
    • http://nobody-films.com/bpms/includes/fckeditor_uploads/userfiles/file/5084542682.pdfIn PDF document text
    • http://gruppocinofilomarsalese.com/userfiles/files/warodawelu.pdfIn PDF document text
    • http://encino.ilovepokebar.com/uploads/files/gufasuximoxodisevo.pdfIn PDF document text
    • http://yakutiaprime.ru/SITE/files/editor/file/93900182168.pdfIn PDF document text
    • http://mhinflatable.com/upload/file/16715500149.pdfIn PDF document text
    • http://jingmingtai.com/filespath/files/20210913153204.pdfIn PDF document text
    • http://micronforgacsolo.hu/UserFiles/file/jakevafe.pdfIn PDF document text
    • https://novahealthclinic.ca/userfiles/file/61638524196.pdfIn PDF document text
    • https://pointswestliving.com/ckfinder/userfiles/files/kuwedebunuwiniwubeta.pdfIn PDF document text
    • https://willes-gb.com/uploads/files/202109012220103840.pdfIn PDF document text
    • http://csc0898.com/userfiles/file/20210908041838_694y8h.pdfIn PDF document text
    • https://usssecuritate.ro/userfiles/file/rusawatusuposotilubi.pdfIn PDF document text
    • https://artinterior.bg/userfiles/file/59537006259.pdfIn PDF document text
    • http://www.ximangsongthao.com/app/webroot/uploads/files/kewefofed.pdfIn PDF document text
    • http://ex2010.com/uploadfile/file/2021091012574673499.pdfIn PDF document text
    • https://demircanticaret.com/userfiles/file/sarexabarituzoxowa.pdfIn PDF document text
    • https://sharmtocairo.com/userfiles/files/kidoferejarunotafu.pdfIn PDF document text
    • http://www.rpv-drachten.nl/files/file/kagoruxumor.pdfIn PDF document text
    • https://thailonghoang.vn/upload/files/zibidalosikopabas.pdfIn PDF document text
    • https://slotpt2.com/contents/files/31139590377.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_off0000dfda.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDFDA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f7f1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF7F1 10524 bytes
SHA-256: 4a443a699435b61ca7796a75de3bf9885ae886d1dd20a5c2a87ab30e4a0737e3
font_02_sfnt_off00011015.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11015 18232 bytes
SHA-256: a53351540015f2895cf60760381f3ac7059fd25f77bb7b61c44310951c1171fc