Malicious PDF — malware analysis report

Static analysis result for SHA-256 bf4aafc7778ffed8…

MALICIOUS

PDF

79.2 KB Created: 2021-09-17 05:54:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 28616f58fe077360841fd1166b5d2cdb SHA-1: 0c8586c1da58bcb597ac16c05b19130dc054e096 SHA-256: bf4aafc7778ffed8f4b7c2775d4e0a39603a23091de1e0e9996b976cd85c359b
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many pointing to disposable hosting or compromised CMS upload directories, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. While no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with techniques used to host malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://smidgel.ru/uplcv?utm_term=frequency+sound+generator+apk PDF link annotation
    • http://willettelaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/2497520572.pdfIn PDF document text
    • http://coimbrasoftware.hu/images/uploads/files/74757554460.pdfIn PDF document text
    • http://giasuthienphuc.com/Images_upload/files/54347827891.pdfIn PDF document text
    • http://vincitydata.com/uploads/ckfinder/files/33464750076.pdfIn PDF document text
    • http://jawarakreasi.com/file/wuzoje.pdfIn PDF document text
    • https://spheresignal.com/app/webroot/userfiles/files/69745511325.pdfIn PDF document text
    • http://idealthailand.com/file_media/file_image/file/12776976077.pdfIn PDF document text
    • https://monarchwinemerchants.com/wp-content/plugins/super-forms/uploads/php/files/578ac69da985d3a3ccdf49eccfefa523/24356237928.pdfIn PDF document text
    • http://envigest.cz/upload/file/judinixiwabazipixawokuba.pdfIn PDF document text
    • http://propertiesforrent.com/userfiles/file///fomovetiboguraw.pdfIn PDF document text
    • https://likeevent.it/writable/public/userfiles/file/44655030706.pdfIn PDF document text
    • http://thesnowmanicecream.com/ckfinder/userfiles/files/vapinamupifupexufa.pdfIn PDF document text
    • https://mancomunidadvaldizarbe.com/userfiles/files/veregijepamilen.pdfIn PDF document text
    • http://zhymwz.com/upfile/file/bixigiminaleso.pdfIn PDF document text
    • http://we2meeting.com/ckfinder/userfiles/publics/files/nizaziretifedojoto.pdfIn PDF document text
    • https://www.hdcorp.com.br/wp-content/plugins/super-forms/uploads/php/files/etu2ccdf9a42l4cot4id770bfm/xowerawitone.pdfIn PDF document text
    • https://www.ferienhof-schneider.de/wp-content/plugins/formcraft/file-upload/server/content/files/16143e0db5e52c---pedar.pdfIn PDF document text
    • http://ilturismoinitalia.it/userfiles/files/35399998582.pdfIn PDF document text
    • http://detaycopymatbaa.com/userfiles/file/famotukowopetovulered.pdfIn PDF document text
    • https://samsungvrvklima.com/upload/ckfinder/files/supepeni.pdfIn PDF document text
    • http://qwerty.pl/_data/file/mifajogemopudexaloxezowi.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_off0000c2c7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC2C7 22668 bytes
SHA-256: d8f967b943c4af274b698163fc320845421d754eafd4204085e0daf69a3ec6b2
font_01_sfnt_off0000fe05.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE05 10980 bytes
SHA-256: 0971568caa8dffb8abc1d51f6579277722b17dac37ca0cf3a5c6122fe46571c8
font_02_sfnt_off00011733.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11733 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1