Malicious PDF — malware analysis report

Static analysis result for SHA-256 86962e66fa6b9e89…

MALICIOUS

PDF

85.0 KB Created: 2021-09-07 23:59:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 34b32965b1099e77f4bdbe8920698d8c SHA-1: 27b8c51f8210462e087a2505d6e7c137edff3429 SHA-256: 86962e66fa6b9e89dde0c2f9f79b8a225531532047587f4542e4132d41d8e653
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains a large number of external links, many of which point to compromised WordPress sites. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to lure users to phishing sites or download further malware. The document body is heavily obfuscated and unreadable, providing no direct user-facing content but the structure and heuristics point to a malicious link farm.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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 https://sieuviet.net/webroot/img/files/90629113071.pdf In PDF document text
    • http://amfmeg.org/wp-content/plugins/formcraft/file-upload/server/content/files/1606cf35b2b9d3---jawuragirejofipuguwuki.pdfIn PDF document text
    • https://www.conkite.com/wp-content/plugins/super-forms/uploads/php/files/d2a893cb2a2abdc1cbb0ce9a03af69cd/xiwekukiz.pdfIn PDF document text
    • http://www.x454.com/wp-content/plugins/super-forms/uploads/php/files/51l5hku7k2sreo6ivpv1auknf2/beviwajotuzexeposijisa.pdfIn PDF document text
    • https://agribusiness.pk/wp-content/plugins/formcraft/file-upload/server/content/files/1608ab03c4020c---46860531725.pdfIn PDF document text
    • https://dukra.sk/editor_uploads/files/7890155773.pdfIn PDF document text
    • https://eclipsetheaters.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609c6faad0e26---mitozerifezefovotisufigep.pdfIn PDF document text
    • http://goref.ru/files/file/nikutiwofumaputagele.pdfIn PDF document text
    • https://propbrains.com/wp-content/plugins/super-forms/uploads/php/files/jcmc3kj3rn0885shpb9sp8cr61/4984553280.pdfIn PDF document text
    • https://arrayamed.com/userfiles/file/92894371628.pdfIn PDF document text
    • http://sireny.net/share/files/korovijimesetek.pdfIn PDF document text
    • http://objetivovender.com/wp-content/plugins/formcraft/file-upload/server/content/files/16088909f6b1f6---duwoxu.pdfIn PDF document text
    • https://bibliothequedesarts.ch/ckfinder/userfiles/files/taxolizerunisadevukukokur.pdfIn PDF document text
    • http://adamlegal.com/userfiles/file/7419328430.pdfIn PDF document text
    • https://local-atlas.ru/userfiles/files/mivorazafebuvigupopef.pdfIn PDF document text
    • http://quickvideo.nl/userfiles/file/gadefomasitusijula.pdfIn PDF document text
    • https://livingcircles.ch/wp-content/plugins/formcraft/file-upload/server/content/files/1609e3badbdc02---9672161877.pdfIn PDF document text
    • http://sarahscupcakery.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612344ec08c18---65009804918.pdfIn PDF document text
    • https://earthideasawnings.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608971b2c7ea0---xepugibugizekitupavunidip.pdfIn PDF document text
    • https://miamivanservice.net/wp-content/plugins/formcraft/file-upload/server/content/files/16096e149a511c---65666733808.pdfIn PDF document text
    • http://movitecnic.fr/ressource/site-image/files/xidadekugakatifowotab.pdfIn PDF document text
    • http://www.barankayalar.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160aa9265aab73---lagozifaji.pdfIn PDF document text
    • https://sweetburden.com/upload/users/files/60991713335.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/PmAiG5ZyT-k/uplcv?utm_term=online+pdf+file+size+mb+to+kb+converterPDF 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_off0000e7c0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE7C0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ffd7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFFD7 11004 bytes
SHA-256: 6631a180bbe59a3c641c3acc73b7eeca55d0ecac93958dec531eae57284cd0b8
font_02_sfnt_off00011939.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11939 17224 bytes
SHA-256: 85bd4a6f4516f8a859266e97e501d1c45cafd153670470f12ea16091181746d1