Malicious PDF — malware analysis report

Static analysis result for SHA-256 85d9f224ee93a62e…

MALICIOUS

PDF

88.0 KB Created: 2021-07-07 13:53:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: 411c4c5ca8643c8062e9d6d4ea6d8f0d SHA-1: a4370f30719f6ec7751f1c2cd221e59090637b54 SHA-256: 85d9f224ee93a62e5d17c22e1e3814b1b721dac7305024d04c322fd70d173584
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1055.012 Process Injection

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The heuristics reveal it functions as a link farm, with numerous URLs pointing to compromised WordPress sites and disposable hosting. These links are likely designed to redirect users to phishing pages or download further malware, aligning with a spearphishing attachment attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9835

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://chcial.ru/uplcv?utm_term=blue+video+hd+background PDF link annotation
    • http://abwplazaview.com/uploads/files/xipuri.pdfIn PDF document text
    • https://www.actionconstructionjax.com/wp-content/plugins/super-forms/uploads/php/files/cd497b56e666d8c5f8a8647aec00946a/tovuvegowivexuzevubi.pdfIn PDF document text
    • https://webhostmurah.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b72922e4599---fomilisadozofe.pdfIn PDF document text
    • https://technok.cz/wp-content/plugins/super-forms/uploads/php/files/b5f91aa3f317a84f7e96a6aa197eea8f/tamuzipojaxaveze.pdfIn PDF document text
    • https://hoakhanh.vn/uploads/image/files/59866932814.pdfIn PDF document text
    • https://asharfilalkulfi.com/ckfinder/userfiles/files/gatobiwufabuwunivavi.pdfIn PDF document text
    • https://joyfool.art/wp-content/plugins/super-forms/uploads/php/files/d88a3d948fe6d481d249011d99b5f93b/79807110084.pdfIn PDF document text
    • https://simovi.mx/wp-content/plugins/formcraft/file-upload/server/content/files/160b8788420ae2---5150631665.pdfIn PDF document text
    • https://yarsan.ru/wp-content/plugins/super-forms/uploads/php/files/8c9a0b10a24705cce0cca936cf5eac15/66469117240.pdfIn PDF document text
    • https://interesttour.com/wp-content/plugins/super-forms/uploads/php/files/9fb0f0acd4e5c43d0af319c7a0dbf743/jivuvufujul.pdfIn PDF document text
    • https://aquariumfargo.com/wp-content/plugins/super-forms/uploads/php/files/263d021b1094f16d578a9df2213d5b58/35760634718.pdfIn PDF document text
    • http://creativeindustries.ru/uploads/userfiles/file/572845339.pdfIn PDF document text
    • http://optimus.org.au/wp-content/plugins/formcraft/file-upload/server/content/files/1608e86ea2b89f---lifenosigeberenudizow.pdfIn PDF document text
    • https://massagetheory.ca/wp-content/plugins/super-forms/uploads/php/files/29f469c6b43e40589e55da5bebbea494/15167607431.pdfIn PDF document text
    • http://www.alfainstal.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1607ab5ace1921---71197234505.pdfIn PDF document text
    • http://inter-travel.hu/_user/file/jemazilosar.pdfIn PDF document text
    • http://cdmatik.com/uploads/file/warovepebakodabepun.pdfIn PDF document text
    • http://goreskyreunion.com/clients/b/ba/ba087d28c24afe6c5bc45fa062332e47/File/vozufaw.pdfIn PDF document text
    • https://specialbrands.gr/wp-content/plugins/super-forms/uploads/php/files/843aabfbf39aeaaa36c628d700d78ddd/mevez.pdfIn PDF document text
    • http://urbanconstructions.org/images/uploadedimages/file/wilalolopujoxa.pdfIn PDF document text
    • http://www.vitrierbxl.be/wp-content/plugins/formcraft/file-upload/server/content/files/1607c118c520fe---zovekexajadil.pdfIn PDF document text
    • https://totalyoumovement.com/wp-content/plugins/formcraft/file-upload/server/content/files/160754fdab7a4b---40625070746.pdfIn PDF document text
    • http://nhs1968.com/clients/65482/File/21542385639.pdfIn PDF document text
    • http://jcaf.or.kr/ckfinder/userfiles/files/32538147524.pdfIn PDF document text
    • http://tiwtactic.com/userfiles/files/76428122808.pdfIn PDF document text
    • http://www.absolutecateringla.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c900a38d241---dofazo.pdfIn PDF document text
    • 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_off0000f71a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF71A 10836 bytes
SHA-256: 1e57410c2d4ed9c5e4772c80237d76f130eb6a224fe2883295698f9d51adc49c
font_01_sfnt_off00010fcd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10FCD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000127df.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x127DF 16588 bytes
SHA-256: 479dd1e32f5aec5079b2e3b8fc7c17308daeaa10317ed889d283421eb842624b