Malicious PDF — malware analysis report

Static analysis result for SHA-256 7b4d287a2a67141f…

MALICIOUS

PDF

81.3 KB Created: 2021-09-19 03:29:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 20ab170c3c52eff976c962fe10f63da1 SHA-1: 8e5b357b86bef40761f3d669884eaf525a8e13c7 SHA-256: 7b4d287a2a67141ffb89969d92efe19bf1f1e708fb9359f1e54d82cfbe1ee67d
156 Risk Score

Malware Insights

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

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate the presence of link farms pointing to compromised websites and disposable hosting, suggesting an attempt to redirect users to malicious content. The embedded URLs, while some are marked benign, contribute to the overall pattern of malicious redirection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9911

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://gabinetortodontyczny.eu/userfiles/file/wemime.pdf In PDF document text
    • http://iranjobex.com/cache/fck_files/file/41312550992.pdfIn PDF document text
    • http://pulsarvn.com/media/ftp/file/xetifoleberozuzijedujepis.pdfIn PDF document text
    • https://mariapolis.net/ckfinder/userfiles/files/33990411314.pdfIn PDF document text
    • http://centreforeffectivecoaching.com/media/file/tixov.pdfIn PDF document text
    • https://www.poolsrus.com.au/application/third_party/ckfinder/userfiles/files/35877714006.pdfIn PDF document text
    • http://tiendanatacion.com/noticias/files/gidag.pdfIn PDF document text
    • http://tomgiongvip.com/uploads/files/file/desufonasog.pdfIn PDF document text
    • http://ikhmongol.mn/ckfinder/userfiles/files/biwanefadedujiw.pdfIn PDF document text
    • https://mehreganimaging.com/images/upload/files/ruzowuferubelikibebuvoxod.pdfIn PDF document text
    • http://szhlfz.net/upload/bamojixip.pdfIn PDF document text
    • https://wamsconference.com/wp-content/plugins/super-forms/uploads/php/files/b2b43afe98696e8dd48c8e95cf1a7bc1/lipilawevinujuvenebiso.pdfIn PDF document text
    • http://lovesenergy.nl/file/46430503194.pdfIn PDF document text
    • http://www.deco-interieure.com/userfiles/file/wozijusujesowobi.pdfIn PDF document text
    • https://rivieresoceanie.com/ckfinder/userfiles/files/tojuzaxape.pdfIn PDF document text
    • http://www.afamaresme.org/wp-content/plugins/formcraft/file-upload/server/content/files/161427d0d6c997---rofivodovesete.pdfIn PDF document text
    • http://uts.edu.co/portal/app/ckfinder/userfiles/files/wefiloju.pdfIn PDF document text
    • http://eskuvotoszkanaban.hu/editor_up/wudugexevinodo.pdfIn PDF document text
    • http://www.bordadoindustrial.com/ckfinder/userfiles/files/92828068684.pdfIn PDF document text
    • https://tmtteks.com/files/14569136343.pdfIn PDF document text
    • http://ljjxmining.com/uploadfile/file///2021091306360881.pdfIn PDF document text
    • https://coachtourbusrental.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613fddca075da---nifixufakatelex.pdfIn PDF document text
    • http://phoiinnhiet.com/images/uploads/files/85748488794.pdfIn PDF document text
    • http://www.amedna.com/userfiles/files/fiperukujifazajifuwe.pdfIn PDF document text
    • http://flyingwedge.com/uploads/assets/file/febuzosaguwuzepijerefed.pdfIn PDF document text
    • https://www.fecomerciomg.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/1612f3569bc78c---35243963679.pdfIn PDF document text
    • http://garantc.ru/userfiles/file/mutunikokor.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/A3Ryygt5BCM/uplcv?utm_term=how+to+switch+on+tablet+without+power+buttonPDF 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_off0000da88.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA88 16944 bytes
SHA-256: 918a3f9d3c8da55784e8df76ebb91deb7cdb3d289a0bee4cfc0c7738cc5d1767
font_01_sfnt_off00010641.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10641 10788 bytes
SHA-256: 755fbbb8cab392891a3ca447f22ed8475161bd6725fb0444a9aabb088d17e942
font_02_sfnt_off00011ede.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11EDE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1