Malicious PDF — malware analysis report

Static analysis result for SHA-256 b6090e3f210505dc…

MALICIOUS

PDF

82.7 KB Created: 2021-08-10 14:05:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-01
MD5: 3a4cc3497124a47bc1ca37a2c7bfc801 SHA-1: ac4903e4807397addfebccd83c9ae0015cb826a7 SHA-256: b6090e3f210505dc418b7da3b40b6e063854ae3d454389cd54cef4ba541b15b3
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories and presents a deceptive download button. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9995

Heuristics 7

  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://southwest66reunion.com/clients/f/f6/f6f8b7bd17d60304c359e527a2c43449/File/nonanonij.pdf In PDF document text
    • https://www.davinci.dk/wp-content/plugins/formcraft/file-upload/server/content/files/160984cdd8cdfc---69172301025.pdfIn PDF document text
    • https://www.agcontraincendios.es//ckfinder/userfiles/files/20698658200.pdfIn PDF document text
    • https://callhfelectric.com/wp-content/plugins/formcraft/file-upload/server/content/files/16098944db5fed---mumilifufezujekerinu.pdfIn PDF document text
    • http://stopasbestos.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160bc1dbfa7129---pimagolax.pdfIn PDF document text
    • https://mission4recruitment.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bab846d0a03---rixarojugitexujesapaliti.pdfIn PDF document text
    • http://decaiyun.com/upload/file/210718145227534401w0yxzgpd3k0y.pdfIn PDF document text
    • https://nstoplana.rs/ckfinder/userfiles/files/xedob.pdfIn PDF document text
    • https://amitadevnani.com/userfiles/file/bebapevuduxasijoguxet.pdfIn PDF document text
    • https://mindweave.co.uk/wp-content/plugins/super-forms/uploads/php/files/s9gua98vh6pg13s0togiujg3cs/97042221665.pdfIn PDF document text
    • http://arcdesantmarti.com/biocop/Images/images-editor/file/bukavivuzunoxoju.pdfIn PDF document text
    • http://meteosputnik.ru/userfiles/file/gijowepuloxakin.pdfIn PDF document text
    • http://townsendrogersfamilyreunion.com/clients/9/91/912616e09393d205379ff76530a10a1f/File/piwepesobawinapovitero.pdfIn PDF document text
    • https://www.ergunaygoren.com/wp-content/plugins/formcraft/file-upload/server/content/files/16081e8b2568ef---ramisa.pdfIn PDF document text
    • http://graphicon.hu/wp-content/plugins/formcraft/file-upload/server/content/files/160d03dd379845---26238379594.pdfIn PDF document text
    • http://hanbangrd.com/userfiles/file/20210724184425_1643330556.pdfIn PDF document text
    • https://plumcourse.com/wp-content/plugins/super-forms/uploads/php/files/b1f14d095d173930f02b133f016b71f8/29755658618.pdfIn PDF document text
    • https://brazilairporttransfers.com/ckfinder/userfiles/files/zigumiroj.pdfIn PDF document text
    • https://smarttactic.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1607aaae03f575---84132330459.pdfIn PDF document text
    • http://jcbcharpentebois.com/ressource/site-image/files/kevatejoj.pdfIn PDF document text
    • https://www.a2zmedical.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160b4bff1357ed---56355220126.pdfIn PDF document text
    • http://www.etoiles-recrutement.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609a29fc6fac8---pewewagulomebenuwigilovi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=hello+brother+telugu+movie+dubbed+in+tamilPDF 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_off0000da01.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA01 18760 bytes
SHA-256: 3d0c99217867253cc67fe1073674f9f759425336a4a3f1020c7803247998ec0f
font_01_sfnt_off00010c05.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10C05 10824 bytes
SHA-256: 1cba00aefe64f56c894b68e6571384e28f6ec902f52d8a6749af9c98ce13f361
font_02_sfnt_off00012489.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12489 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1