Malicious PDF — malware analysis report

Static analysis result for SHA-256 8ac8bfa3cf62c7ee…

MALICIOUS

PDF

75.4 KB Created: 2021-09-15 23:49:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 2ffe948ff34c5bbf015d26453c3e31dd SHA-1: 44062303248641578b5424aa6a471a8e50965832 SHA-256: 8ac8bfa3cf62c7eedc707fd1df22545eefbc5d8d0a0f877dfdb74bb39337705c
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to disposable hosting or compromised CMS upload directories, indicating a link farm designed to redirect users to malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware delivery. No scripts were extracted, but the structure and URL patterns are indicative of a malicious PDF.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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 http://asupuro.com/user_data/image/file/dinawuvadupexog.pdf In PDF document text
    • http://www.siscbolivia.com/admin/uploaded/fck/file/numupafoxaputaxeminevage.pdfIn PDF document text
    • http://aow.infogestnet.it/ckfinder/userfiles/files/gipebeguw.pdfIn PDF document text
    • https://www.saenger-ohg.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613ce3770b350---29108410795.pdfIn PDF document text
    • http://uhorder.com/upload/files/79888270744.pdfIn PDF document text
    • http://soupworld.de/upload/file/71844556719.pdfIn PDF document text
    • https://spherule.org/wp-content/plugins/super-forms/uploads/php/files/ef2mtic7vf9rus7qeqinahffj2/70006290553.pdfIn PDF document text
    • http://azstorestudio.com/uploads/files/nogigijazif.pdfIn PDF document text
    • https://www.superioreagle.com/wp-content/plugins/formcraft/file-upload/server/content/files/161348a487d6e0---sovotugosapaw.pdfIn PDF document text
    • http://www.sas.edu.mn/ckfinder/userfiles/files/78833307069.pdfIn PDF document text
    • http://zjbfjt.com/upload/files/30135496817.pdfIn PDF document text
    • https://radiosmile.hu/upload/file/20523328043.pdfIn PDF document text
    • http://marymo.ru/uploads/files/woveb.pdfIn PDF document text
    • https://specialgarden.ro/userfiles/file/pajabikurifuzabetizavol.pdfIn PDF document text
    • http://www.pethouse.es/ckfinder/userfiles/files/31638455881.pdfIn PDF document text
    • http://studiotecnicoarduini.eu/userfiles/files/79992706505.pdfIn PDF document text
    • https://sapsda.com/SapmaUserfiles/file/jamiraza.pdfIn PDF document text
    • http://emilygrilltogo.com/uploads/files/wakodeweje.pdfIn PDF document text
    • https://recapress.com/ckfinder/userfiles/files/39721265548.pdfIn PDF document text
    • http://www.feniuniversity.edu.bd/app/webroot/ckfinder/userfiles/files/kupututipibeweda.pdfIn PDF document text
    • https://atcotourismtravel.com/userfiles/file/93304271081.pdfIn PDF document text
    • https://weyergans-hcc.lv/userfiles/file/retepi.pdfIn PDF document text
    • http://fujieshubao.com/zk/UploadFile/file/2021090113035073499.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3CAf4wW3hvY/uplcv?utm_term=freddy+in+space+2+downloadPDF link annotation
    • 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_off0000c0b4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC0B4 18344 bytes
SHA-256: 41a337a41294241a20b6019313c530ccad1a1863c3b0662d741a9da67c7bee35
font_01_sfnt_off0000ef0f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF0F 10704 bytes
SHA-256: fc297fa7789417dbcb5a9a8e1b750be95d620d4c7e11b78ad862b92cc831cc12
font_02_sfnt_off000107d3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x107D3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1