Malicious PDF — malware analysis report

Static analysis result for SHA-256 bfc08e0cae603e58…

MALICIOUS

PDF

68.3 KB Created: 2021-10-08 00:14:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: f05fbecc11067fb09e747056410d427e SHA-1: b458305aceb995064dc32635cab7a78561b76893 SHA-256: bfc08e0cae603e5832cc40d2b6bcbb8e6e5e80455ffa40c4c0993883868c4fa8
146 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.001 User Execution: Malicious Link

The PDF is identified as a phishing lure due to its small size, image-heavy content, and embedded clickable actions. Multiple heuristics indicate it functions as a link farm, directing users to various potentially malicious PDF files hosted on disposable domains. The ML classifier and ClamAV detection strongly support its malicious nature, likely serving as a delivery mechanism for further compromise.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9851

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
  • Image-only document with action trigger (screenshot lure) medium PDF_IMAGE_LURE
    PDF has 1 image(s), only 0 text block(s), carries a click-outward action, and is only 68 KB — typical shape of a phishing lure where a full-page screenshot hides a clickable button that launches or submits to an attacker URL.
  • 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://naasschoolofmotoring.com/fckeditor/userfiles/file/12005005559.pdf In PDF document text
    • http://kaushalacademy.org/ckfinder/userfiles/files/mateduwukolusaditubikomu.pdfIn PDF document text
    • https://www.rapn.ru/ckfinder/userfiles/files/87462510810.pdfIn PDF document text
    • http://brandnewgoods.net/userfiles/file/93190512816.pdfIn PDF document text
    • https://costabravas.com/uploads/localidades/files/jekuxanelolekopot.pdfIn PDF document text
    • http://cageart.ca/wp-content/plugins/formcraft/file-upload/server/content/files/161532316c5543---14065730980.pdfIn PDF document text
    • http://marketingnews.fr/images/file/7311367829.pdfIn PDF document text
    • https://escolaalfa.com/userfiles/file/74462212736.pdfIn PDF document text
    • http://www.unidacardoso.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1614d1551d40c6---radifuratevi.pdfIn PDF document text
    • http://trubaopt.ru/content/file/79044037279.pdfIn PDF document text
    • https://karate2.cdmedia.pl/userfiles/file/32240712805.pdfIn PDF document text
    • http://xn--80aafmoni2biho.xn--p1ai/admin/ckfinder/userfiles/files/vabezevoxisut.pdfIn PDF document text
    • http://dulichtantai.com/files/uploaded/files/7488046277.pdfIn PDF document text
    • https://avukatwebsitesi.kocgrafik.net/upload/files/lodevoposikego.pdfIn PDF document text
    • http://anhhieu.vn/hinhanh/file/weviz.pdfIn PDF document text
    • http://urbanelect.com/userfiles/file/zoxuzefodofebizewa.pdfIn PDF document text
    • https://etonbio.com/newsLetters/images/file/43684793269.pdfIn PDF document text
    • http://akgwealthplanner.com/crm/files/69880046883.pdfIn PDF document text
    • http://ideviceplus.nl/app/webroot/files/userfiles/files/16999640956.pdfIn PDF document text
    • http://phuvuongcorp.com/luutru/files/pazikezizogederetunava.pdfIn PDF document text
    • http://prmakeup.com/Image/files/tepufezadijam.pdfIn PDF document text
    • https://fotokeramika.bg/userfiles/file/74450273535.pdfIn PDF document text
    • http://ekopaczka.pl/imgbrama/files/nuvawefesevi.pdfIn PDF document text
    • http://szjglaw.com/uploadfile/file/2021100300442073499.pdfIn PDF document text
    • http://innovad-ltd.com/userfiles/file/sukitawezobewojemokuxeli.pdfIn PDF document text
    • http://p-itos.net/admin/userfile/image/file/18966347219.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3CAf4wW3hvY/uplcv?utm_term=cousins+of+compiler+pdfPDF 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_off0000b14d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB14D 13832 bytes
SHA-256: 22019b6028babb176be740c8f795173bd0e3c573e701c4637df222916911a22c
font_01_sfnt_off0000d34c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD34C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000eb63.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB63 10652 bytes
SHA-256: 79b80e4bfe0e6c4d1f329d3674a5c2328809dd3d9d529b21b924f24d87d0ed7e