Malicious PDF — malware analysis report

Static analysis result for SHA-256 a7f4e4d4009c87bf…

MALICIOUS

PDF

73.1 KB Created: 2021-09-13 00:20:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 0b4a13197727fd045f71024ba78cadd4 SHA-1: 736eb6d7a4a5958ac6f819b2d89ce20f05dabeb8 SHA-256: a7f4e4d4009c87bfff968ba7a91f7310c3163dbb17c649f35643bb12c33d44cb
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm, with many URLs pointing to potentially compromised websites or disposable hosting, suggesting a phishing or malware distribution scheme. The document body was unreadable, but the presence of numerous external links strongly supports the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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 https://energiadirect.pl/application/resources/ckfinder/userfiles/files/77483715255.pdf In PDF document text
    • https://tonerihned.cz/userfiles/file/jutovanizubigudud.pdfIn PDF document text
    • http://ancheng-medical.com/uploadfile/files/mesuzilabifef.pdfIn PDF document text
    • http://splhardware.com/UploadFile/file/2021090506313873499.pdfIn PDF document text
    • http://orvositudasbazis.eu/images/upload/file/8149012477.pdfIn PDF document text
    • http://kramor.bg/userfiles/file/vorajitimusife.pdfIn PDF document text
    • https://www.gsccn.it/wp-content/plugins/formcraft/file-upload/server/content/files/161309fd5c2938---sawabugedep.pdfIn PDF document text
    • https://maintogelonline2.com/contents/files/navozanufif.pdfIn PDF document text
    • http://teedinmaesai.com/user_img/file/fivitaroti.pdfIn PDF document text
    • http://stroisvias.ru/userfiles/file/keravinokokole.pdfIn PDF document text
    • https://kipass.fr/userfiles/file/68318837820.pdfIn PDF document text
    • https://mindweave.co.uk/wp-content/plugins/super-forms/uploads/php/files/fksariu3rouibap6gp5moh300j/82220565378.pdfIn PDF document text
    • https://lanegarrett.net/userfiles/file/tavoge.pdfIn PDF document text
    • https://jjcfurnituremaker.com/userfiles/files/zuwaniduweserikivex.pdfIn PDF document text
    • http://inphuduong.vn/upload/files/28152554786.pdfIn PDF document text
    • http://sntaviator.ru/ckfinder/userfiles/files/389202317.pdfIn PDF document text
    • https://www.rougeindigo.com/ckfinder/userfiles/files/bafigoxojabezirofux.pdfIn PDF document text
    • https://moveo-sport.pl/userfiles/file/vaparuperurezumali.pdfIn PDF document text
    • https://mi-stores.com/basketballtotaal/images/editor/file/wofupenunebubi.pdfIn PDF document text
    • http://www.appsolutely.sg/wp-content/plugins/formcraft/file-upload/server/content/files/1613c58819fe8f---kugokotitilelotanabavagu.pdfIn PDF document text
    • http://xn--80aadq3ae7aa5k.xn--p1ai/upload/file/dulive.pdfIn PDF document text
    • http://salonorganica.ru/upload/files/pomudadodikan.pdfIn PDF document text
    • http://richmore.kr/uploadfile/fckeditor/file/37896104214.pdfIn PDF document text
    • https://mebelihome.ru/upload_picture/fobozosagitabo.pdfIn PDF document text
    • https://at-studio.tw/app/webroot/userfiles/files/20210903_065632.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/A3Ryygt5BCM/uplcv?utm_term=cinema+mortal+kombatPDF 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_off0000bb03.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBB03 17400 bytes
SHA-256: c6287ea2906bc0b9239a65d615ac50d74b2e7bd0898a8ba82a769dd77aa77c70
font_01_sfnt_off0000e79d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE79D 10364 bytes
SHA-256: 1975cf56db6bf0025b11196dd78545e74dbee9ad6bf814cf7981498acce685b5
font_02_sfnt_off0000ff01.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFF01 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1