Malicious PDF — malware analysis report

Static analysis result for SHA-256 3e99c73324499fff…

MALICIOUS

PDF

64.2 KB Created: 2021-06-21 04:16:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-25
MD5: 4fd1f77e173f6f06cc3b65416bbc4f03 SHA-1: 3c9a847d39f933d01de19b21c5e6d4ae70c73009 SHA-256: 3e99c73324499fff8b73c140dbde4bed8f3381b32abd1f8940586ea89a8419eb
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains a link farm pointing to multiple compromised websites and disposable domains, suggesting an attempt to distribute malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. The document body itself is heavily obfuscated and does not provide clear instructions, but the presence of numerous external links is the primary indicator of malicious activity.

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://www.tomasjelinek.com/img/pub/file/devaxuteb.pdf In PDF document text
    • https://www.etbsupplies.com/wp-content/plugins/formcraft/file-upload/server/content/files/160844e528d8cb---63081639280.pdfIn PDF document text
    • https://legacyltg.com/wp-content/plugins/super-forms/uploads/php/files/f9c89bf9be4f22e0fa642070fd4166c6/gawupi.pdfIn PDF document text
    • https://www.drserapkagan.com/wp-content/plugins/super-forms/uploads/php/files/3ggdik5dg8vjuf7cp52ib0i0nv/mazeniresekojelanujewez.pdfIn PDF document text
    • https://alphaveneers.co.uk/wp-content/plugins/super-forms/uploads/php/files/eeaef56c8d2bae6d85b04f48970702b9/zosojuri.pdfIn PDF document text
    • https://www.kalirich.com/wp-content/plugins/super-forms/uploads/php/files/uk88094p7o2j3g6p59a139dgi6/61574776376.pdfIn PDF document text
    • http://fouladsazanco.com/Upload/file/fanuna.pdfIn PDF document text
    • http://wtmongolia.com/materials/file/mubuwulolebituvivum.pdfIn PDF document text
    • http://beautybybelief.com/admin/images/file/suxezevidikuwefewegigigim.pdfIn PDF document text
    • http://apartmaji-zunicmile.com/uporabnik/file/pojevexurite.pdfIn PDF document text
    • http://www.medical-psychology.gr/wp-content/plugins/formcraft/file-upload/server/content/files/160a7f69290cc6---94646862597.pdfIn PDF document text
    • http://texmet.pl/userimages/file/25749280872.pdfIn PDF document text
    • http://graphicon.hu/wp-content/plugins/formcraft/file-upload/server/content/files/16071ef3c8664c---7376317764.pdfIn PDF document text
    • https://alshamiltrading.com/alshamilfiles/file/dugebixe.pdfIn PDF document text
    • https://humble-brag.com/wp-content/plugins/super-forms/uploads/php/files/0ike47a53ceihr0mt8kquuq2o8/98111442865.pdfIn PDF document text
    • http://smclassof57.org/clients/34860/File/mobopujejidaxepes.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/BvfzZFkJO3s/uplcv?utm_term=ohms+law+practice+problems+worksheet+with+answers+pdfPDF 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_off0000bd75.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBD75 5716 bytes
SHA-256: fd8d8cd0cb7979ce840cb78db2a579444310a233590ec04752d36cf6fc513c73
font_01_sfnt_off0000d0cc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD0CC 10060 bytes
SHA-256: 69722e90ea4b21309b0a0f709f45fc92eb580de92d6397039c82fa26ee56372a