Malicious PDF — malware analysis report

Static analysis result for SHA-256 687f23d0bea8dafb…

MALICIOUS

PDF

67.3 KB Created: 2021-05-12 16:03:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-21
MD5: ce49646a9b76dfd92cdc2171efaf1841 SHA-1: 7828bb442907a99446f48e7ddaa60fa063018a79 SHA-256: 687f23d0bea8dafba8ad0117a4bbcf16663b9f664a346053f035806d2e4451b0
156 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. The heuristics reveal it functions as a link farm, directing users to multiple compromised WordPress sites and potentially disposable hosting domains. While no scripts were explicitly extracted, the nature of PDF link farms often involves embedded JavaScript to facilitate redirection or exploit vulnerabilities, aligning with T1059.007. The overall pattern suggests a phishing or malware distribution attempt, likely delivered as a spearphishing attachment (T1566.001).

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 6

  • 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.
  • 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://kingspec.su/wp-content/plugins/super-forms/uploads/php/files/eomeiqsm3241s2abpcegu56sol/60237085260.pdf In PDF document text
    • http://perfectthesale.com/wp-content/plugins/formcraft/file-upload/server/content/files/160946eadbda2d---54055900562.pdfIn PDF document text
    • https://wills.sg/wp-content/plugins/super-forms/uploads/php/files/e549a79b03320f3c355540753b4f955f/dopedine.pdfIn PDF document text
    • http://conservationenergy.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608bea3b543c5---dimidiw.pdfIn PDF document text
    • https://trsbarriersdirect.com/wp-content/plugins/super-forms/uploads/php/files/0nfabrmipniae8sl3gl25unim9/paverosasatejigupejegita.pdfIn PDF document text
    • http://bascobrunswick.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16093a519694a7---55879342210.pdfIn PDF document text
    • https://accuratesearch.com/userfiles/file/53278028971.pdfIn PDF document text
    • https://avenirpourtous.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1606fb8aa3bf19---fizujirevemo.pdfIn PDF document text
    • https://www.parkgest.ch/wp-content/plugins/formcraft/file-upload/server/content/files/1607957a660abd---29787443546.pdfIn PDF document text
    • http://akgikorea.com/file_upload/fck_upfile/file/59720891314.pdfIn PDF document text
    • https://www.ltgpartners.com/wp-content/plugins/super-forms/uploads/php/files/a20e9334b39623e514182080dbfd95be/1887795716.pdfIn PDF document text
    • https://primeodontorj.com/wp-content/plugins/super-forms/uploads/php/files/338c61fc2cc3f663524bb565e1a585f4/fetefonijajes.pdfIn PDF document text
    • https://finestblogger.de/wp-content/plugins/super-forms/uploads/php/files/l9asjuj6n9ogonqnnafhjoaio9/fugakajetuneb.pdfIn PDF document text
    • http://antik-cafe-bergen.de/wp-content/plugins/formcraft/file-upload/server/content/files/1608b4cc8afd11---rubofagoguguvovibinuz.pdfIn PDF document text
    • http://www.victorian-manor.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/16097ce07b3da2---72348897282.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/skout/mBVl/~3/fzgW7-mxBc0/uplcv?utm_term=verizon+stock+performance+2018PDF 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_off0000ca8d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCA8D 5728 bytes
SHA-256: fc98af00d319dd680754be13e8e31d87bf66b632d5e69f02885cea2dbed23a92
font_01_sfnt_off0000de11.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE11 10116 bytes
SHA-256: f09b11dac4fa4f57e94f3e06c2b46c6aab035978f2bc2ff8ca1adb5623caf1ed