Malicious PDF — malware analysis report

Static analysis result for SHA-256 57f6b98cce865af1…

MALICIOUS

PDF

90.2 KB Created: 2021-10-08 01:13:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 9a089dd01f365a937b91e3e608c08008 SHA-1: 41bd2356b489a9d53cc958eb61e6db67a1b5a32b SHA-256: 57f6b98cce865af13e3f71106ac919d77335b8197352d60a3b7aeb14caf24251
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which are part of a link farm hosted on disposable domains, as indicated by the PDF_SEO_DISPOSABLE_LINK_FARM heuristic. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or distributing further malware. While no scripts were explicitly extracted, the nature of the embedded URLs and the link farm structure points towards a malicious document designed to lure users to potentially harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9822

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://huntic.ru/uplcv?utm_term=pdf+for+electronics+and+communication+engineering PDF link annotation
    • https://thailonghoang.vn/upload/files/86570838672.pdfIn PDF document text
    • http://alarmy-kamery24.pl/userfiles/file/21274002271.pdfIn PDF document text
    • https://chineseclothingonline.com/File/kowowitajof.pdfIn PDF document text
    • http://sunrui-ti.com/d/files/dekejetekobigebelema.pdfIn PDF document text
    • http://miroslaws.com/ckfinder/userfiles/files/nakelegodu.pdfIn PDF document text
    • http://sfipl.in/userfiles/file/xugexukomelirosupowopulof.pdfIn PDF document text
    • https://rajatotogroup1.com/contents/files/58718731430.pdfIn PDF document text
    • https://ibrahimkoc.com/images/Media/files/14083503250.pdfIn PDF document text
    • http://www.peritaonline.es/ckfinder/userfiles/files/42626791962.pdfIn PDF document text
    • https://koltoztetes-szallitas-lomtalanitas.excore.hu/ckfinder/userfiles/files/56763714948.pdfIn PDF document text
    • https://mgs-on-track.com/app/webroot/userfiles/file/86126256572.pdfIn PDF document text
    • http://ikkosushi.com/uploads/files/7141128894.pdfIn PDF document text
    • https://www.alongsideasia.com/wp-content/plugins/super-forms/uploads/php/files/a91997bd061e43c34fa27e62db18f731/85167930224.pdfIn PDF document text
    • http://cestovni-postylka.eu/userfiles/file/zosawi.pdfIn PDF document text
    • http://855solution.com/htdocs/cljr/data/files/54851353671.pdfIn PDF document text
    • http://araulmor.tel-cor.com/images/library/file/lovusiriri.pdfIn PDF document text
    • http://clairvoyantinfotech.com/demo/images/94268300725.pdfIn PDF document text
    • http://www.siscbolivia.com/admin/uploaded/fck/file/15961006568.pdfIn PDF document text
    • http://usefchina.com/uploadfile/file///2021091712164658.pdfIn PDF document text
    • https://manage3.realtourvision.com/rtv/ckfinder/userfiles/images/files/68621972979.pdfIn PDF document text
    • http://krukaiart.com/userfiles/files/7101575420.pdfIn PDF document text
    • http://revucue.com/ckfinder/userfiles/files/61278173018.pdfIn PDF document text
    • http://adaviestransportltd.com/userfiles/file/88594129072.pdfIn PDF document text
    • http://farashimirooz.com/files/fexibikifetanud.pdfIn PDF document text
    • http://ceraunavoltapizzeria.it/userfiles/files/jexirirutanafe.pdfIn PDF document text
    • http://xn--9w3b11kh5l.com/ckupload/files/miwuvex.pdfIn PDF document text
    • http://jinistudy.com/_UploadFile/Images/file/jepiwosadaxur.pdfIn PDF document text
    • http://balie.overeembv-profielen.nl/upload/files/98681548285.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_off0000f6ea.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF6EA 10920 bytes
SHA-256: 69f11885d841a365a9d473d75cb82c794aad66f4ef991e6ee9719924b7b86ea4
font_01_sfnt_off00010ff6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10FF6 19384 bytes
SHA-256: b4c9f50a8361ae3d503d84a3db78eb541c63f19d77e753092404dd867f337f76
font_02_sfnt_off000142dc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x142DC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1