Malicious PDF — malware analysis report

Static analysis result for SHA-256 6a97ad85e1a9c88a…

MALICIOUS

PDF

95.2 KB Created: 2021-06-27 00:01:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-20
MD5: 11a91911a6363bcfbe50b1773779d29d SHA-1: 79573fa0939bdc6a8962c1c6cdadd94a272537a7 SHA-256: 6a97ad85e1a9c88a653adcb31fd36802486f7d42db6413e2bc790fcab3e422f2
156 Risk Score

Malware Insights

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

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, directing users to multiple external websites, many of which are hosted on compromised WordPress installations. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, suggesting it's not intended for direct user reading but rather to host links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9820

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://annjulieskarpmo.com/userfiles/file/zojimid.pdf In PDF document text
    • http://rusiuojigalvoji.lt/wp-content/plugins/formcraft/file-upload/server/content/files/1607676a4df538---51491678712.pdfIn PDF document text
    • https://parisautotravel.com/wp-content/plugins/super-forms/uploads/php/files/bgu4rrnhumcl44njvmsj76jv40/tasuluzemowepuzer.pdfIn PDF document text
    • http://julieesteban.com/wp-content/plugins/formcraft/file-upload/server/content/files/16073d690f0532---1584522404.pdfIn PDF document text
    • https://forex-robo.org/wp-content/plugins/super-forms/uploads/php/files/787a00f0f98dd676d108cfed73769659/ninivunazagafufumep.pdfIn PDF document text
    • http://www.hcibatiment.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1608d3c2a54a9c---3562462072.pdfIn PDF document text
    • https://wscnaturalhealings.com/wp-content/plugins/super-forms/uploads/php/files/4ff2fa7ccaf01e86788aed8df63cbc89/45493120521.pdfIn PDF document text
    • https://www.guestquesttravelmedia.com/wp-content/plugins/super-forms/uploads/php/files/hrjg9ga6nj22vcruiqd7rf2fo6/lofojipogako.pdfIn PDF document text
    • http://primebrokeragetx.com/ckfinder/userfiles/files/dubukixazakizuribi.pdfIn PDF document text
    • https://grand-forge.ru/wp-content/plugins/super-forms/uploads/php/files/d087fbde79c3d446debbd1c0793b7ce8/jamapuwu.pdfIn PDF document text
    • https://hacunamatata.ru/wp-content/plugins/super-forms/uploads/php/files/e9f64d983fc9d4b97cb36b8163303de9/87568528871.pdfIn PDF document text
    • https://psychotherapie-dr-albrecht.de/wp-content/plugins/formcraft/file-upload/server/content/files/1609153fbedcb7---mezosude.pdfIn PDF document text
    • http://www.britocunhaadvocacia.com.br/home/wp-content/plugins/formcraft/file-upload/server/content/files/160c0f1e50b587---rorop.pdfIn PDF document text
    • http://mko-yug.ru/wp-content/plugins/super-forms/uploads/php/files/ecb048dc18d67c6a14617eb070a0ca5d/nobovonubep.pdfIn PDF document text
    • https://pavaniautismschools.com/wp-content/plugins/super-forms/uploads/php/files/90fhkinoine84sr6hqtueraddv/17742230627.pdfIn PDF document text
    • http://crystal-lamp.ru/uploads/files/62069427227.pdfIn PDF document text
    • http://applecentervn.com/uploads/image/files/3448391631.pdfIn PDF document text
    • https://impariant-club.ru/wp-content/plugins/super-forms/uploads/php/files/dddb48679aa0990d05423942fd79960a/fimilura.pdfIn PDF document text
    • http://www.nuricomuvakfi.org/wp-content/plugins/super-forms/uploads/php/files/1t8gb5pi47ak4mdjra5le3b106/fikafa.pdfIn PDF document text
    • https://nicemexico.net/wp-content/plugins/formcraft/file-upload/server/content/files/16079ebcf0e89c---10512813084.pdfIn PDF document text
    • https://www.audifonosdoshoydos.com/wp-content/plugins/formcraft/file-upload/server/content/files/16086f8db43601---vetabovugutowegafelujaso.pdfIn PDF document text
    • https://spectrumohio.com/wp-content/plugins/super-forms/uploads/php/files/7ddcca2ffa728d382f30a04b03fab3bc/80511221942.pdfIn PDF document text
    • https://careersourceokaloosawalton.com/files/public/83832104201.pdfIn PDF document text
    • http://www.medicalalliedtraining.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a929e870905---xazuvupases.pdfIn PDF document text
    • https://www.wikiwebagency.it/wp-content/plugins/super-forms/uploads/php/files/b8071a5f1d4326aac4c826315d89fc09/86581476419.pdfIn PDF document text
    • https://www.lumisolar.pe/wp-content/plugins/formcraft/file-upload/server/content/files/160bc2623a3a7a---35974579050.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/LPIa9PGmDLg/uplcv?utm_term=cindy+trimm+commanding+your+morning+declarations+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_off00010fe4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10FE4 17280 bytes
SHA-256: a723f0031882e0a1a6e8b67b07004b2807aa57785ceada264f82b767969e6af1
font_01_sfnt_off00013ce8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13CE8 11208 bytes
SHA-256: bb3cb42e2bfd22378ca04ad1fec3df97c060a3ffdd06baec52eda59857c4efba
font_02_sfnt_off000156fd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x156FD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1