Malicious PDF — malware analysis report

Static analysis result for SHA-256 74b21bafefd03fbb…

MALICIOUS

PDF

79.1 KB Created: 2021-09-05 13:45:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 893199cefc0dadd0e23fc8d2e5424b71 SHA-1: b90a309d00fea79662b372463fd0476e6e6443c1 SHA-256: 74b21bafefd03fbbd3e6f69050af7d4f5e96fc298f554bad2c79e40dc4c2e196
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1190 Exploit Public-Facing Application

The PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and an ML classifier indicated a high probability of maliciousness. Heuristics indicate the PDF contains a link farm pointing to compromised WordPress upload storage, suggesting it's used to distribute malicious content. The presence of multiple unknown URLs hosted on compromised sites reinforces the phishing or malware distribution vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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 https://nscs.org/wp-content/plugins/super-forms/uploads/php/files/47dd1018c056e529aff5cac4d88f9079/kevexawimagamelusitoz.pdf In PDF document text
    • http://rencontres-icare.org/userfiles/file/mikuw.pdfIn PDF document text
    • https://jamiatulbanat.in/wp-content/plugins/formcraft/file-upload/server/content/files/16073467fbd0ab---vedirugewanag.pdfIn PDF document text
    • https://soosekszer.hu/upload/files/33752946673.pdfIn PDF document text
    • http://www.shipsupply.co.mz/wp-content/plugins/formcraft/file-upload/server/content/files/16082ac2ea1292---genasofesoxepi.pdfIn PDF document text
    • https://www.rydalmereprestige.com.au/wp-content/plugins/super-forms/uploads/php/files/aivcukm4fgo6rkfi60nu7rhvkg/31137841246.pdfIn PDF document text
    • https://advancedbusiness.co/wp-content/plugins/super-forms/uploads/php/files/706edfc05bb06e8b5a6402be934b9e63/moxuvosikagebalowoganifet.pdfIn PDF document text
    • http://sunrui-ti.com/d/files/vakilinasebamanip.pdfIn PDF document text
    • http://www.pianoszimmermann.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1608218d27c815---zinasevuzuvegezod.pdfIn PDF document text
    • http://cinebuzz.be/uploads/userfiles/files/23317385026.pdfIn PDF document text
    • http://wksystems.net/HotelEstimator/userfiles/file/54454454986.pdfIn PDF document text
    • https://adbadog.com/wp-content/plugins/super-forms/uploads/php/files/8eb33ab7a5fa87896860bb8f17adcfd4/vofodajetosiroz.pdfIn PDF document text
    • http://www.greddy.com/admin/common/ckfinder/userfiles/File/61737497714.pdfIn PDF document text
    • http://www.urbanwaterways.info/files/pozuxof.pdfIn PDF document text
    • https://www.siemers-deutschmann.de/wp-content/plugins/super-forms/uploads/php/files/208gll1i83tf92ni6qco92m37s/36242473.pdfIn PDF document text
    • https://lokmangal.co.in/wp-content/plugins/super-forms/uploads/php/files/f5db9dd8e58b0a3afeff602cb57223de/jibikidezosup.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/PmAiG5ZyT-k/uplcv?utm_term=centrelink+medical+certificate+pdf+su415PDF 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_off0000d010.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD010 11148 bytes
SHA-256: ef0458c4cd8e6a9b6ddb5b7fda05547417d27d8cb738f34257114e74f2f581d5
font_01_sfnt_off0000ea36.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA36 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010248.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10248 17504 bytes
SHA-256: eba898c75efef1d69d89536d57375e42b42fc0e208e3ba4c98852e72c55208e6