Malicious PDF — malware analysis report

Static analysis result for SHA-256 5b636c9fe631c67d…

MALICIOUS

PDF

73.7 KB Created: 2021-09-16 05:18:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 08b417e1d02b76808ad8ba6d28bc2741 SHA-1: eb18143380d0dbe39ff9923925e4216f105947ab SHA-256: 5b636c9fe631c67d64855b56b99c91fe5f81d606a483e1fb496a20d1d29a80f1
184 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file contains embedded JavaScript and numerous external URLs, many of which are hosted on compromised CMS upload storage or disposable hosting, indicating a link farm for phishing or malware distribution. The ML classifier and ClamAV detection strongly suggest malicious intent. The embedded JavaScript likely facilitates the redirection to these malicious URLs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 8

  • 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) documents that carry no urgency or charge/dispute escalation.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://crysiq.ru/uplcv?utm_term=radha+avtar+book+in+gujarati+pdf+download PDF link annotation
    • http://www.canadiantreasurer.com/wp-content/plugins/formcraft/file-upload/server/content/files/16134058da2a64---sosapagafegu.pdfIn PDF document text
    • http://ceramkgres.ru/userfiles/file/51932907013.pdfIn PDF document text
    • http://vtracauto.com/wp-content/plugins/formcraft/file-upload/server/content/files/16138a3ee0d2e5---14809836477.pdfIn PDF document text
    • http://abbeytraining.net/userfiles/file/pifoxegajazuguvovifizex.pdfIn PDF document text
    • https://xn--80apefbdm9ah5g.xn--p1ai/userfiles/savago.pdfIn PDF document text
    • http://nanchang.chinatupai.com/web/js/ckfinder/userfiles/files/73332536360.pdfIn PDF document text
    • https://kapefashion.com/files/files/lolerul.pdfIn PDF document text
    • https://observatoire-omic.org/documents/file/niwodutiwadelurumexeme.pdfIn PDF document text
    • http://www.akutrans.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613b78e218cc4---49365414317.pdfIn PDF document text
    • https://aspirecambodia-edu.org/userfiles/file/46154642465.pdfIn PDF document text
    • https://pfgmm.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16141d10b3bdaf---sobotawofoxigavinanir.pdfIn PDF document text
    • https://www.chauffeur-prive-nice.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1613ca6ad534e4---kuluropatava.pdfIn PDF document text
    • https://gulf-rope.com/images/bulk_images/files/jilazapaziluvijevowim.pdfIn PDF document text
    • https://manajrgvaaradhi.com/cms-uploads/files/polilavitukuwivix.pdfIn PDF document text
    • http://www.kowel.com/ckfinder/userfiles/files/1631256116.pdfIn PDF document text
    • http://brodart01.com/wp-content/plugins/super-forms/uploads/php/files/cqmchsgp2veb6f2lmh0jbudl2k/45489710483.pdfIn PDF document text
    • https://dsodrecital.com/wp-content/plugins/formcraft/file-upload/server/content/files/161356cc095940---wudedewobike.pdfIn PDF document text
    • http://cleannshieldflorida.com/wp-content/plugins/super-forms/uploads/php/files/75669a191a2eef3b880d768aaf757dff/95101659583.pdfIn PDF document text
    • http://xz-brand.com/ckfinder/userfiles/files/31213027639.pdfIn PDF document text
    • https://idealist.ro/userfiles/file/vikeru.pdfIn PDF document text
    • http://worshipedia.mobi/sites/default/files/file/buwatadok.pdfIn PDF document text
    • https://teplitsyoptom.ru/wp-content/plugins/super-forms/uploads/php/files/ec3b5eeb5aba84bcf5fcf6416adcf69b/mukumurorepu.pdfIn PDF document text
    • http://sweethomedelivery.com/ckeditor/ckfinder/core/connector/php/uploads/files/99263258554.pdfIn PDF document text
    • https://alzubidi.com/userfiles/files/nutumewunudaxizukisupa.pdfIn 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://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_off0000b889.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB889 17564 bytes
SHA-256: e170906ccb5790506d5d439e017ea0329bfcc8de70d3f45d23e9c1dd013351a5
font_01_sfnt_off0000e573.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE573 11136 bytes
SHA-256: e48cfa66621b1c0f8a4a8261ae29f9bcc3bfe0b5b814e7c35782157b307667ac
font_02_sfnt_off0000fef1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFEF1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1