Malicious PDF — malware analysis report

Static analysis result for SHA-256 43664c3e86807998…

MALICIOUS

PDF

101.6 KB Created: 2021-07-23 07:47:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: 899baf7981cc854ff3a51e6c81df9f59 SHA-1: 95ce2ecea6f66d0849b6e3f1f75b0b152e89aa10 SHA-256: 43664c3e86807998cd0c002d183a56041808c1dc49891516c76faffe8ab39367
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many of which point to compromised WordPress upload directories. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The presence of multiple distinct hosts and a link farm structure suggests an attempt to obscure the ultimate destination or to leverage SEO poisoning.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9937

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://bilagroup.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a6d64e4d3f6---24326043962.pdf In PDF document text
    • http://ophirtonhotel.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160a94f0ada327---pasakurejibat.pdfIn PDF document text
    • http://jewfri.kr/files/image/files/86065372024.pdfIn PDF document text
    • http://codemessaging.net/ckfinder/userfiles/files/zogoxorivemikogonowax.pdfIn PDF document text
    • https://vntdc.com/upload/fck/file/kolazabazaxofuxadexomeril.pdfIn PDF document text
    • https://numen-wow.com/userfiles/cloud//files/najesupajunizumow.pdfIn PDF document text
    • http://arcdesantmarti.com/biocop/Images/images-editor/file/dotigezi.pdfIn PDF document text
    • https://evg-prague.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160a9a2943732c---vupojov.pdfIn PDF document text
    • http://terapeutickemasaze.eu/wp-content/plugins/formcraft/file-upload/server/content/files/16092069b4045a---gonez.pdfIn PDF document text
    • http://olsztyntransportmedyczny.pl/userfiles/file/tezenumuwumebadexobo.pdfIn PDF document text
    • https://beaumont-residence.com/wp-content/plugins/super-forms/uploads/php/files/m89fkkre27c7lc66beo6675g46/52934838786.pdfIn PDF document text
    • https://www.marthatrotts.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16076617d7fe21---pobopuvelegipukagi.pdfIn PDF document text
    • http://thevenetianmask.com/clients/71561/File/nutobozopibetev.pdfIn PDF document text
    • https://www.avenueroadadvertising.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ac9acbf2fa8---fawitesuxagepuvub.pdfIn PDF document text
    • https://www.reliancecareuk.com/wp-content/plugins/super-forms/uploads/php/files/d2e76a3b4a02b5c89ef8e0a49611bae6/76319572518.pdfIn PDF document text
    • https://123kozijnofferte.nl/wp-content/plugins/super-forms/uploads/php/files/dflu1ddlog325svhj2va0e1t23/favaxuwinikerokapu.pdfIn PDF document text
    • http://erfolgsapp.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607b65a01d882---46360920247.pdfIn PDF document text
    • https://soudurelausiere.ca/upload/editor/file/rojatenez.pdfIn PDF document text
    • https://abril.pe/wp-content/plugins/super-forms/uploads/php/files/r8jm2mpo9mrt3hvegmk01dvn26/rafuforozolozemipinan.pdfIn PDF document text
    • http://www.esthemed.ch/wp-content/plugins/formcraft/file-upload/server/content/files/1607f2cdf1602d---3927768425.pdfIn PDF document text
    • https://www.bluegreenshouseboats.in/wp-content/plugins/formcraft/file-upload/server/content/files/1609d9b9bf11bf---67977811904.pdfIn PDF document text
    • http://www.petersmetalstitching.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1607041cf7f7a6---dezoxixavopipune.pdfIn PDF document text
    • https://fablab808.com/nbloom/fckuploads/file/12130335501.pdfIn PDF document text
    • http://erex.hu/upload/file/wiseteloboxejiporig.pdfIn PDF document text
    • http://jullien38.com/ressource/site-image/files/febujeborowezisitezejidig.pdfIn PDF document text
    • http://atlantichomeportugal.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607295baea928---76518331105.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1KS0DP0cxss/uplcv?utm_term=bjt+in+ltspicePDF 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_off0001273e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1273E 19152 bytes
SHA-256: b9428fdc63f4d705cb3977a754817d1b7bec13890d205acb0d6f0d3c4e5ffa7a
font_01_sfnt_off00015845.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15845 10168 bytes
SHA-256: ecce4a9e7f20eb239ba07106df8fff86137bb1d61043e05b379feea1bc30c08e
font_02_sfnt_off00016f14.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16F14 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1