Malicious PDF — malware analysis report

Static analysis result for SHA-256 3f8ea8da67345cb2…

MALICIOUS

PDF

95.0 KB Created: 2021-07-09 17:31:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: 72f13f60b14895470c024ce3e9d3a7dd SHA-1: 3129e6ff79b4c67bfdf8630a7b5c9eb60582f879 SHA-256: 3f8ea8da67345cb262286e8418d1130810ea444368f220d31fe786277aad9e21
176 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm and contains a callback lure, prompting users to call a phone number in a deceptive context. While no scripts were directly extracted, the presence of numerous links to potentially compromised WordPress sites suggests an attempt to host or distribute further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9957

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.
  • 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) or Microsoft license-boilerplate documents that carry no urgency or charge/dispute escalation.
  • 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.medical-psychology.gr/wp-content/plugins/formcraft/file-upload/server/content/files/160e5311a33182---13188466307.pdf In PDF document text
    • http://alexandercdg.com/clients/36029/File/19384206245.pdfIn PDF document text
    • http://jnnycc.org/userfiles/file/gusalidikexerexow.pdfIn PDF document text
    • http://www.sunarsurdurulebilir.com/wp-content/plugins/super-forms/uploads/php/files/8q5att1vf0gv5ig2ga82d5ktb7/21948627725.pdfIn PDF document text
    • http://www.christinemartin.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160a41fb1401bd---fatovapitizivoki.pdfIn PDF document text
    • http://prodesign31.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1606c888563c96---37034791155.pdfIn PDF document text
    • http://www.hotel-margherita.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ab7031d1a57---zejasinano.pdfIn PDF document text
    • https://rclurie.com/wp-content/plugins/super-forms/uploads/php/files/b3149baacff7261aa5dcca9a05643d7c/juberazo.pdfIn PDF document text
    • http://boulderdivorcelaw.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f68a8360a2---nubinuto.pdfIn PDF document text
    • https://travels-ukraine.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bda16282c83---10508354990.pdfIn PDF document text
    • http://bracyfamilyreunion.com/clients/c/c2/c2db1a97f769835965582c74015c7782/File/xokutuxubejigepi.pdfIn PDF document text
    • http://wf515345.tw/CKEdit/upload/files/rajorukugozokafib.pdfIn PDF document text
    • https://smarttactic.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1608e392f0f61c---wodogogekipawabibako.pdfIn PDF document text
    • https://travolution.travel/wp-content/plugins/super-forms/uploads/php/files/53676d827e191edadc43df03831bc060/12005735184.pdfIn PDF document text
    • http://bazis-expertiza.ru/ckfinder/core/connector/php/files/65021924725.pdfIn PDF document text
    • https://lynnesnaturaltreats.com.au/wp-content/plugins/super-forms/uploads/php/files/a65279f6df2a9509bdbe9083436f1b29/77981364841.pdfIn PDF document text
    • https://tkpmission.org/wp-content/plugins/formcraft/file-upload/server/content/files/160a0765052f81---81616172588.pdfIn PDF document text
    • https://www.arc-welding.co.uk/wp-content/plugins/super-forms/uploads/php/files/e3ufnf1t95nofvumtrhv2g57k7/9246524899.pdfIn PDF document text
    • https://al-farh-iq.com/upload/userfiles/file/53527730187.pdfIn PDF document text
    • https://daleel.global/wp-content/plugins/super-forms/uploads/php/files/8rdkq62v9d731p711vrrsgcgan/48180027500.pdfIn PDF document text
    • http://onnetsolution.in/userfiles/file/redeturujevotatumajesomax.pdfIn PDF document text
    • http://logisticsnetworks.net/ckfinder/userfiles/files/rafedati.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/FevRqgeaUVY/uplcv?utm_term=ucsd+parking+lot+mapPDF 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_off00010d21.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10D21 18524 bytes
SHA-256: 507615cd79b2fe05f44f9974252c2278b745edd40c8eefcdb017db19f02d7378
font_01_sfnt_off00013e5a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13E5A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00015671.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15671 10824 bytes
SHA-256: 6375cd32fe8dc2cfe6c42727696c5480aafd37cc1d041246a910bc4511bce341