Malicious PDF — malware analysis report

Static analysis result for SHA-256 66845833643e603d…

MALICIOUS

PDF

93.9 KB Created: 2021-07-31 18:11:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 5d315d918742d425430292086988d757 SHA-1: 1abf64e663b766117eb8c8de40f53b99509afa89 SHA-256: 66845833643e603da70d2a384ba90f2960b0e6584c9fbbfdeabfc3c8743a7a55
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a link farm pointing to compromised WordPress upload storage, suggesting a phishing or malware distribution attempt. The heuristic 'SE_INVOICE_LURE' indicates the document's content is designed to deceive users into clicking the malicious links. No scripts were extracted, but the presence of multiple external URIs and the ML classifier's high confidence score support the malicious verdict.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9925

Heuristics 7

  • 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.
  • Fake invoice / payment lure low SE_INVOICE_LURE
    Document contains invoice or payment language paired with an action verb — useful context when combined with link, macro, or attachment indicators
  • 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://www.adatechotomasyon.net/wp-content/plugins/formcraft/file-upload/server/content/files/160a2735157f60---67129631669.pdf In PDF document text
    • http://adams-gold.ru/archive/image/file/71380838093.pdfIn PDF document text
    • http://lavera.it/wp-content/plugins/formcraft/file-upload/server/content/files/160a0124f17b37---tuwelijexel.pdfIn PDF document text
    • https://www.properties-thassos.com/wp-content/plugins/super-forms/uploads/php/files/qrqujsepdvrgt64uvmffj5l8sm/jimosugopuvovogobatuti.pdfIn PDF document text
    • http://iltorg.ru/upload/file/79951610410.pdfIn PDF document text
    • http://emaaravm.net/upload/files/80872335454.pdfIn PDF document text
    • https://tramhuonghanoi.vn/upload/files/80713177223.pdfIn PDF document text
    • http://ctyrkolky-gamax.cz/data/dokumenty/ruritefewad.pdfIn PDF document text
    • https://thesmithgrouphouston.com/wp-content/plugins/super-forms/uploads/php/files/29b43b7455c17ecad54c0020da5cc3ad/tofepofevazawubavofusowav.pdfIn PDF document text
    • http://vibrosystem.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1607248076df3b---74912322866.pdfIn PDF document text
    • http://lightofislamonair.org/uploads/files/vipizezegi.pdfIn PDF document text
    • https://realwebguys.com/wp-content/plugins/formcraft/file-upload/server/content/files/16084208914dec---15754101450.pdfIn PDF document text
    • https://bokseinstituttet.dk/wp-content/plugins/formcraft/file-upload/server/content/files/160ac340b869cb---gadodajiwimugofor.pdfIn PDF document text
    • http://kencert.vn/uploads/image/files/fufugipefi.pdfIn PDF document text
    • https://sellerflows.com/wp-content/plugins/super-forms/uploads/php/files/362c682b9fda81ef2ed0813870b8e04d/41380762620.pdfIn PDF document text
    • https://butchercurnow.com/img/shop//contents/wugoxezamuzazigilizere.pdfIn PDF document text
    • https://siphouse96.com/wp-content/plugins/super-forms/uploads/php/files/55f0ee2bf231a21b8678954c998a8a63/legitafi.pdfIn PDF document text
    • http://sbhs1967.com/clients/8/89/8985ce50e7417da620f75e2af787291b/File/45474635883.pdfIn PDF document text
    • https://www.dishdivvy.com/wp-content/plugins/super-forms/uploads/php/files/aaccdb4f5be82a845e21f00539d9207a/wugufugigisakolalit.pdfIn PDF document text
    • https://seroinstitute.com/wp-content/plugins/super-forms/uploads/php/files/53051b4aed77dc73113c0ac0715c639a/mosuxemonejafatara.pdfIn PDF document text
    • http://inspirationallabels.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16081b18696002---jagezudelutaga.pdfIn PDF document text
    • http://winteringlawoffice.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/30286373518.pdfIn PDF document text
    • https://dtcprojects.com.au/wp-content/plugins/super-forms/uploads/php/files/nhf71o4o8jo1ajre8n9ni8gids/dolifadufebagusive.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/fzgW7-mxBc0/uplcv?utm_term=roblox+hilton+hotel+training+guide+receptionistPDF 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f554.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF554 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010d66.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10D66 19260 bytes
SHA-256: e4a96752e2668f70d0a60f0405d841ca5930c5848b1b9d937fc0fada82342005
font_02_sfnt_off00013ed5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13ED5 3860 bytes
SHA-256: 51bc4a887cd273c9dbbdaa4e6cb27282966723876f155d95ae958137b0dc502d
font_03_sfnt_off00014e2a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14E2A 11180 bytes
SHA-256: f09a0253920fff65f09299f35c7f0bd9ddd87b536645313b4f9b750ffc38aece