Malicious PDF — malware analysis report

Static analysis result for SHA-256 6f4459ddcb748b35…

MALICIOUS

PDF

93.8 KB Created: 2021-09-10 07:13:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 45ce74e57455a2dea3420e6435a07c52 SHA-1: dca892475bba6c6221f25a48aa7f1e556738db8a SHA-256: 6f4459ddcb748b3500117bdf9c6763fe03d6613c56c799411ee84003aca7ee18
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

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

Machine Learning

  • Nyx PDF Classifier malicious score 0.9969

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://www.recetasyconsejos.com/wp-content/plugins/formcraft/file-upload/server/content/files/16138817cead1c---solizakelaxijawufotixigo.pdf In PDF document text
    • http://dush-kz.ru/uploads/fck/file/215433323.pdfIn PDF document text
    • http://zulassung4you.de/bilder/file/jimosamikofenofe.pdfIn PDF document text
    • http://resheto.ru/users_images/fck/file/lavelarikeluziwosovamexiv.pdfIn PDF document text
    • http://china-guolin.com/filespath/files/20210908154545.pdfIn PDF document text
    • https://nikken-engineer.jp/export/sd205/www/jp/r/e/gmoserver/8/6/sd0748886/nikken-engineer.jp/fckeditor/upload/file/nemofalol.pdfIn PDF document text
    • http://sonhanint.com/uploadpic/sun/files/202109091405107599.pdfIn PDF document text
    • https://blugarden.eu/file/zujebewitavawu.pdfIn PDF document text
    • http://paletydozahrady.cz/ckfinder/userfiles/files/sakamujerolaxebax.pdfIn PDF document text
    • https://pgp-puh.hr/fck_media/file/lotaxifen.pdfIn PDF document text
    • http://ximangsongthao.com.vn/app/webroot/uploads/files/bujenabek.pdfIn PDF document text
    • https://pepsima.biz/files/file/65504119998.pdfIn PDF document text
    • https://pemaboutiquehotel.com/assets/userfiles/files/8881867110.pdfIn PDF document text
    • http://ttccid.com/userfiles/file/buworagasikowil.pdfIn PDF document text
    • http://bk-plus.at/userfiles/files/siwobudox.pdfIn PDF document text
    • http://www.johnrealestate.in/ckeditor-ckfinder-integration/uploads/files/27735930507.pdfIn PDF document text
    • http://www.saraviation.com/wp-content/plugins/formcraft/file-upload/server/content/files/161333191ebea5---71858499738.pdfIn PDF document text
    • https://yuktiedu.com/wp-content/plugins/super-forms/uploads/php/files/66d054c05cb69c9413cda81d36c965c1/rufuwepabuze.pdfIn PDF document text
    • http://baheth24aqari.com/ckfinder/userfiles/files/lusotozujoxofarinuvimof.pdfIn PDF document text
    • https://baobiachau.com/luutru/files/65510224640.pdfIn PDF document text
    • http://mrybalko.ru/files/giboxowi.pdfIn PDF document text
    • https://mvpartners.be/images/uploadedimages/file/libevadudopi.pdfIn PDF document text
    • https://stehovani-ostrava.cz/static_pages_files/file/48429587291.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/FevRqgeaUVY/uplcv?utm_term=never+let+go+moviePDF 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_off00010cae.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10CAE 18000 bytes
SHA-256: 5ae8de2c76a8b3cf5d9354e0fe2f83ef1755e12b9c8de8c98c4bd38029535435
font_01_sfnt_off00013b56.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13B56 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001536d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1536D 10060 bytes
SHA-256: 8a7bf877e91afb6183c379cd2a445516cb99d1101c4d02c01c3d6ee607d41597