Malicious PDF — malware analysis report

Static analysis result for SHA-256 861efadb93d0e984…

MALICIOUS

PDF

87.0 KB Created: 2021-07-03 12:34:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: f7cb7f53869283337bd28aab96b8422b SHA-1: b699b84b5f650bc843c22a65e571adb71e018e2a SHA-256: 861efadb93d0e984be340a7026d2d8d4ac96cbc712b28fa36b52ed780bc6c98f
156 Risk Score

Malware Insights

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

The PDF contains numerous links pointing to compromised CMS uploads and disposable hosting, indicative of a link farm designed to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly support its malicious nature. The embedded document body is heavily obfuscated and unreadable, providing no direct textual clues to the specific lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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://pwr-tech.ru/userfiles/file/pezagari.pdf In PDF document text
    • http://www.drop-lok.com/wp-content/plugins/formcraft/file-upload/server/content/files/160adcb72f2213---zoradubeberozijo.pdfIn PDF document text
    • https://solarconsulting.org/wp-content/plugins/super-forms/uploads/php/files/548b74b2d2d6791fd0c054378f1f8c99/85240971694.pdfIn PDF document text
    • http://www.annaleehuber.com/content_files/file/70196337779.pdfIn PDF document text
    • http://seoulsquare.com/userfiles/file/fetovuluzerevegozomosi.pdfIn PDF document text
    • http://lamekatus.ee/uploads/ckeditor/files/bibalapuzilozekatibufizo.pdfIn PDF document text
    • https://jamiatulbanat.in/wp-content/plugins/formcraft/file-upload/server/content/files/160986f20a2448---wobuxapabadelo.pdfIn PDF document text
    • https://oknoplus-omsk.ru/wp-content/plugins/super-forms/uploads/php/files/cc9b8b6734611597d656afd450756bf4/68493938788.pdfIn PDF document text
    • https://ecomassage.pt/wp-content/plugins/super-forms/uploads/php/files/o11v26mksgb3bjomco0rq246q1/lulafitit.pdfIn PDF document text
    • http://madmojo.com/fckupload/file/56296774026.pdfIn PDF document text
    • http://gbagencement.fr/uploads/file/venesodotomawipojazapij.pdfIn PDF document text
    • https://www.inter-tube.co.uk/wp-content/plugins/super-forms/uploads/php/files/61bf1c8a0c3d70432d4d21f4c73c5a38/napifomonuxetelijawud.pdfIn PDF document text
    • https://pensionatiitalianiinportogallo.it/wp-content/plugins/super-forms/uploads/php/files/057e4a27dfbee403e2e8f908e2d33463/biterulavuve.pdfIn PDF document text
    • http://zaun-produzent.de/userfiles/file/24489214504.pdfIn PDF document text
    • http://uat.ideadunes.com/projects/ideadunes-portfolio-site/wp-content/plugins/formcraft/file-upload/server/content/files/160bfdb785beb0---funuwanarefisudopixabuzo.pdfIn PDF document text
    • https://mszukam.pl/dat//file/negilapibotegovupodaru.pdfIn PDF document text
    • https://artsketch.ru/wp-content/plugins/super-forms/uploads/php/files/436bb5c6a6606dac3ecbba139dd692fc/taxananumexu.pdfIn PDF document text
    • https://spheresignal.com/app/webroot/userfiles/files/tevike.pdfIn PDF document text
    • http://littlepearlspublishing.in/data/eimages/file/bawawi.pdfIn PDF document text
    • https://teplitsyoptom.ru/wp-content/plugins/super-forms/uploads/php/files/a1f2aa7eccf300fd50a87cd7768e4081/2323518304.pdfIn PDF document text
    • https://twr1115.net/files/fckeditor/file/87628206400.pdfIn PDF document text
    • http://elitvorota.ru/f/file/negateti.pdfIn PDF document text
    • https://n95america.com/wp-content/plugins/super-forms/uploads/php/files/da28c95bde2876eb4ff1e87a9be13d99/bizitujezuvudi.pdfIn PDF document text
    • https://spaslask.pl/wp-content/plugins/super-forms/uploads/php/files/ci7gut82l338dpuhskmnbperch/26030138267.pdfIn PDF document text
    • https://worldkelo.com/wp-content/plugins/super-forms/uploads/php/files/aabb6d6812b0775c15a7c36ecc98ac27/60616032367.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BvfzZFkJO3s/uplcv?utm_term=comprehensive+home+science+class+10+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://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_off0000f013.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF013 11060 bytes
SHA-256: fd1fc91a1e0ad3afa92b9552086df0458b5bc36ccf25065b168d2b7990497a40
font_01_sfnt_off000109ab.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x109AB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000121bd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x121BD 17116 bytes
SHA-256: 9407554a8360d5db0c1baf9ecfa08b4da64404fb210ff87236d5bb5411219127