Malicious PDF — malware analysis report

Static analysis result for SHA-256 ac15b5de154a643a…

MALICIOUS

PDF

79.9 KB Created: 2021-06-09 17:18:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-11
MD5: 0120ecae5ba8b13df15b2bcfe339f6e9 SHA-1: fc92de9a48c97f331a6da42d9d72f70b314deff8 SHA-256: ac15b5de154a643afea5617600ac58201141bca3b2cc2bb1963f6235d7dd5139
156 Risk Score

Malware Insights

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

The PDF file contains a large number of embedded links, many pointing to compromised WordPress sites and disposable hosting, suggesting a link farm or phishing lure. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware distribution via these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://wastran.ru/uplcv?utm_term=ldc+model+paper PDF link annotation
    • https://www.beadvised.co.uk/wp-content/plugins/super-forms/uploads/php/files/323d950f7c8183bd1a51d9415da2e5ac/samesegavopixesafagutot.pdfIn PDF document text
    • http://kaufdeinauto.de/wp-content/plugins/formcraft/file-upload/server/content/files/1609b348b5d35e---56351607621.pdfIn PDF document text
    • https://www.avenueroadadvertising.com/wp-content/plugins/formcraft/file-upload/server/content/files/160900fff7bfc4---jugufanuju.pdfIn PDF document text
    • http://www.grupohk.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160a9223fbaebe---nizorebugupaxeze.pdfIn PDF document text
    • https://iguanapools.com.au/wp-content/plugins/super-forms/uploads/php/files/34vumtm5i50va4hl7ku30rbcpr/62007868291.pdfIn PDF document text
    • http://actionelectric.pt/www/wp-content/plugins/formcraft/file-upload/server/content/files/1609f789659ec1---11954504712.pdfIn PDF document text
    • http://malbreil.com/userfiles/file/10142302460.pdfIn PDF document text
    • http://curry-box-deluxe.de/userfiles/file/lugenisimotizaxemezele.pdfIn PDF document text
    • https://vakukh.ru/wp-content/plugins/super-forms/uploads/php/files/561ae9e3072953f816c77122178ec684/22967057640.pdfIn PDF document text
    • https://oknoplus-omsk.ru/wp-content/plugins/super-forms/uploads/php/files/74bee9d7c0dd50bc727f288af400a3e3/nerakonipifefikof.pdfIn PDF document text
    • https://istanbulbalbir.com/upload/ckfinder/files/55015635733.pdfIn PDF document text
    • https://www.sir.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1608097dbaaab1---fenuzage.pdfIn PDF document text
    • http://www.ponderosafestival.com/wp-content/plugins/formcraft/file-upload/server/content/files/160854879a1704---27154454714.pdfIn PDF document text
    • http://ipvoicenj.com/wp-content/plugins/formcraft/file-upload/server/content/files/160893095c4d1e---14862903888.pdfIn PDF document text
    • https://iescolumbus.org/wp-content/plugins/super-forms/uploads/php/files/a48fdcfc118a6807b2e488198d40c7e7/32379251274.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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://scripts.sil.org/OFLIn 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_off0000e764.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE764 4980 bytes
SHA-256: 790ef53a1755c87b05c54983416e7193a4d9771fa7512b526ebba01ea3913b64
font_01_sfnt_off0000f83e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF83E 10996 bytes
SHA-256: ce2f3e3cbc460f8660011af9db85d501af57bf5025fa759a10b1124efa56f0d6
font_02_sfnt_off00011de8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11DE8 16092 bytes
SHA-256: c9557d91917e40dbb2ce09b7ef560a04a9a832ffe2ebcac6b50408a58351272e