Malicious PDF — malware analysis report

Static analysis result for SHA-256 bc8ab11d6ea4b897…

MALICIOUS

PDF

82.5 KB Created: 2021-06-21 13:06:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-14
MD5: b8f592cc797e513c9626f761030c7ecd SHA-1: f7b84b99f7906f6bdb459bfbc3d6bf0986d3d4d9 SHA-256: bc8ab11d6ea4b89739e307a6e2ed5433696133ae6e4cf783ce8e4d01dfa82ea7
156 Risk Score

Malware Insights

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

This PDF file was flagged by multiple heuristics and a machine learning classifier as malicious, with ClamAV identifying it as Pdf.Phishing.Trojan. The numerous embedded URLs point to compromised WordPress sites and disposable hosting, suggesting a link farm designed to redirect users to malicious content. The document body, though heavily obfuscated, contains references to wkhtmltopdf and creation dates, indicating it was likely generated programmatically to serve as a lure.

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://sk-developers.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a91174c96ce---jogawugarosisege.pdf In PDF document text
    • https://mangonebike.com/uploads/file/fapopasusutugezazujekiju.pdfIn PDF document text
    • http://ciaooo.ru/uploades/userfiles/file/bilezalanixapijozu.pdfIn PDF document text
    • https://martybermanassociates.com/wp-content/plugins/super-forms/uploads/php/files/7158e3749b9b440feb8dfcc1151b2cc7/36450205224.pdfIn PDF document text
    • https://emergent-partners.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b08fcddf22c---porumikotorimeberewur.pdfIn PDF document text
    • https://roweryelectra.eu/app/webroot/uploads/file/16202319745155.pdfIn PDF document text
    • https://www.jemelectric.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b6321bd3a6b---xesuzisedewoxetosetimune.pdfIn PDF document text
    • https://kayakbranson.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608eeb8cdf265---29658315509.pdfIn PDF document text
    • https://bowenpainter.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a9d4e8ac178---davawuluforebanukofagum.pdfIn PDF document text
    • https://itracmediav5.com/ckfinder/userfiles/files/82600954197.pdfIn PDF document text
    • https://rfcorporation.net/wp-content/plugins/super-forms/uploads/php/files/99bae06eb9f5e5f2686a30568db31285/vofizolez.pdfIn PDF document text
    • http://gelateriacool.it/userfiles/files/3285005906.pdfIn PDF document text
    • http://www.lbf-cosmetics.com/website/wp-content/plugins/formcraft/file-upload/server/content/files/1609837d00636b---ruwiloralilofaverumow.pdfIn PDF document text
    • http://cleannshieldflorida.com/wp-content/plugins/super-forms/uploads/php/files/f6c6a898c9622d04732ebcf67ddbcc53/47250452054.pdfIn PDF document text
    • https://lisacutler.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607e359cb7b47---21467684180.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1xuhb7AK25c/uplcv?utm_term=anker+powercore+fusion+5000+manualPDF 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f5e7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF5E7 5572 bytes
SHA-256: 02bba8e580b5351d624917190c550b5de65196fecbbfe99dafe26fcff5f8fa59
font_01_sfnt_off000108e7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x108E7 21288 bytes
SHA-256: 38226027b07cf186e97ad3e5a08a981ceef1479b12204e85def21ddf152a289e