Malicious PDF — malware analysis report

Static analysis result for SHA-256 ff1283557ac2be8c…

MALICIOUS

PDF

70.3 KB Created: 2021-09-07 06:30:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 9abd6986b9c908de242726d53b7e55bd SHA-1: efb7a73da1ba72391657b7ae5bb293d17fb43e37 SHA-256: ff1283557ac2be8c997ceffe8e5114d6c67e2ce32b0e6ccd303acbe8c62ee0c2
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains numerous links to compromised websites, many of which are hosted on WordPress installations utilizing the 'formcraft' plugin for file uploads. ClamAV detected this file as 'Pdf.Phishing.Trojan', and ML classifiers also flagged it as malicious. The primary function appears to be directing users to download further malicious content from these compromised sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.6664

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
  • 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
  • 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://inchirieriavioane.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16085fbf2b686c---gijosoniritixaraloponuraf.pdf In PDF document text
    • https://specialbrands.gr/wp-content/plugins/super-forms/uploads/php/files/b16c025c4871c3c3d1f8498c001e23bf/23064642232.pdfIn PDF document text
    • http://www.linkkorea.co.kr/wp-content/plugins/formcraft/file-upload/server/content/files/1607b4949549e1---lopotelawiwadusurapo.pdfIn PDF document text
    • http://cavusofis.com/images_upload/files/rudininujixarumuxezotavif.pdfIn PDF document text
    • http://tks-forever.com/upload/2021/07/26/file/86759142811.pdfIn PDF document text
    • http://baharemadinah.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a1214985b8b---lofolubasimos.pdfIn PDF document text
    • http://dermalab.pl/userfiles/file/jofinifajovegowebiri.pdfIn PDF document text
    • http://studioghittigargnano.com/userfiles/files/kubuwimewikupixizunaxuked.pdfIn PDF document text
    • https://www.bocamvigliesrooms.com/wp-content/plugins/super-forms/uploads/php/files/a3bbdd37a6d345ee51239eb14abc0fd0/63921843231.pdfIn PDF document text
    • https://aprenda-atdi.com/uploads/files/sezezazuvisolafexafav.pdfIn PDF document text
    • https://dhesient.com/media/bedejagoterujenotex.pdfIn PDF document text
    • http://www.sospapa24.com/lib/ckfinder/imgupload/files/37954002863.pdfIn PDF document text
    • http://studiofelician.com/userfiles/files/wuvovut.pdfIn PDF document text
    • http://www.nationaalgolfcongres.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16083f3347cb7a---wovije.pdfIn PDF document text
    • http://immopolignano.lu/images/xujivelawa.pdfIn PDF document text
    • http://www.lukoilmarine.com/ckfinder/userfiles/files/48602066970.pdfIn PDF document text
    • https://rosycaffe.com/file/fojagilolasavirepomon.pdfIn PDF document text
    • https://gfow.om/wp-content/plugins/super-forms/uploads/php/files/pt5vi6jre05uk13kf2k1fsjc0p/nugamevosubusobumof.pdfIn PDF document text
    • https://travels-ukraine.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a85554aa406---lowetosozivanisulawuzuf.pdfIn PDF document text
    • http://phenix-security.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160894325abb41---75752453165.pdfIn PDF document text
    • https://adiwirawanbali.com/wp-content/plugins/super-forms/uploads/php/files/0a68f1f3a64bb8d7a9890b49e4a4fc34/15740947533.pdfIn PDF document text
    • http://kaufdeinauto.de/wp-content/plugins/formcraft/file-upload/server/content/files/16094acc90212b---nodinilinapumol.pdfIn PDF document text
    • http://mastersequipments.com/ckfinder/userfiles/files/21486783144.pdfIn PDF document text
    • https://csom.cz/wp-content/plugins/super-forms/uploads/php/files/03b60c121c75b90dc7a002e04c7bb678/vadipoluxuxivo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/ngfLrbzwjls/uplcv?utm_term=online+merge+two+pdf+filesPDF link annotation
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d830.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD830 10788 bytes
SHA-256: f05ee2d9580d2b2f44fd91d5cc0a6277a1083041ddb42ace30c0b5f995a780de
font_01_sfnt_off0000f0d7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF0D7 16844 bytes
SHA-256: 9ee351f6f27dc47ef6669b4f705b8e9c30fa265ca87caaeb3049aad4cd912149