Malicious PDF — malware analysis report

Static analysis result for SHA-256 50c61ba5d14a4c36…

MALICIOUS

PDF

72.5 KB Created: 2021-06-24 10:44:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 821437fb05db0108c08692887796651d SHA-1: bb563832e4dcb3d67f3d1d89094c725b63c2b8ce SHA-256: 50c61ba5d14a4c36a704e80a44c08591f9ab13cdc2c89377988309b6a0a4cb97
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

This PDF document contains lures for fake invoices and callback phishing, suggesting it is part of a phishing campaign. It links to multiple external URLs, some hosted on compromised WordPress sites, indicating an attempt to redirect users to malicious content. The ML classifier strongly flagged this PDF as malicious.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 8

  • PDF link to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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.
  • Callback phishing phone lure medium SE_CALLBACK_LURE
    Document asks the user to call a phone number in billing, refund, subscription, fraud, or security context — consistent with callback phishing or tech-support scam patterns. Suppressed for legitimate-issuer (IRS/gov/official-form) documents that carry no urgency or charge/dispute escalation.
  • 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 https://terravistahometeam.com/wp-content/plugins/super-forms/uploads/php/files/0bb4c545664f44bb98dc1a8a2c482e8b/xorenuwixolebaduxevufole.pdf
    • http://www.europesolidaire.eu/userfiles/files/xibalefuw.pdf
    • http://jhsclassof63.com/clients/c/c8/c8cc7cee7579ddcd469b669c0eb172d8/File/libikurufonapovexikopusi.pdf
    • http://chikatere.com/Upload/files/numorusogabola.pdf
    • http://www.kmclogistics.com/wp-content/plugins/super-forms/uploads/php/files/fb4216f7cd3c5a659687d72df472dc5b/waxivarewupamijesofawip.pdf
    • https://www.karavanlakesfet.com/wp-content/plugins/super-forms/uploads/php/files/506d29d94c85f0670c994c21b1a053d0/32825094061.pdf
    • http://sun-tes.ru/files/file/bijujusepeberezufug.pdf
    • http://romanakladatelstvi.cz/userfiles/file/77162712809.pdf
    • https://pensionatiitalianiinportogallo.it/wp-content/plugins/super-forms/uploads/php/files/4cc495ebd6b30df78289b103501dbb0c/sorazodun.pdf
    • https://www.ideaklinikankara.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606ff0c67a258---21282637088.pdf
    • http://fincasotilloviejo.es/files/sotillo/_repo/file/51996326220.pdf
    • http://hopkins1983.com/clients/861771/File/10644302514.pdf
    • http://hillsdalehorseboarding.com/ckfinder/userfiles/files/rebavu.pdf
    • http://viprealestatebrokers.com/userfiles/files/lidevevowetewe.pdf
    • https://www.generalutilities.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607952ff98ef8---39873532503.pdf
    • http://akbmodel.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bd87fede2de---5533252058.pdf
    • https://webvitamin.vn/app/webroot/uploads/files/88445138760.pdf
    • http://www.sunarnuricomuisvealisverismerkezi.com/wp-content/plugins/super-forms/uploads/php/files/ehqm110b2tkjbp4gnr609p8p60/dulubonamavoge.pdf
    • https://emergent-partners.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ac58a84cbd7---22684351466.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://feedproxy.google.com/~r/Uplcv/~3/cv9VXjIrmdE/uplcv?utm_term=gst+remittance+form+pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000dede.bin
e90ba2973ae9d3395ac24d141e9ac005f1a48d99f35a393a9c1e3fb2cba241b8
pdf-font-stream PDF embedded font (sfnt) at offset 0xDEDE 5300 bytes
font_01_sfnt_off0000f0d2.bin
051aa9b48cb03089b00147a1fd0b3daa373ac62c5221884815d2dbed69337165
pdf-font-stream PDF embedded font (sfnt) at offset 0xF0D2 10508 bytes