Malicious PDF — malware analysis report

Static analysis result for SHA-256 a6b4ee0f07c89ffd…

MALICIOUS

PDF

83.6 KB Created: 2021-09-13 02:22:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 58694c6884d5e7f62dcd9a86f6e27bb1 SHA-1: 0b0f188a945cda70056b211bdeb95a1e9c1357ad SHA-256: a6b4ee0f07c89ffdae7917d07a9134965acbed2218e98416a879f2915b9f90eb
156 Risk Score

Malware Insights

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

The PDF contains numerous links pointing to compromised websites and disposable hosting, indicating a link farm designed to redirect users. The ClamAV detection and ML classifier strongly suggest malicious intent, likely for phishing or distributing further malware. The presence of external URI heuristics and link farm indicators confirms the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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://www.hippocratio.gr/ckfinder/userfiles/files/jomepajajuzuz.pdf In PDF document text
    • https://www.hit-education.com/wp-content/plugins/super-forms/uploads/php/files/actfegdi72js12kvoh4l7m2nep/25603495701.pdfIn PDF document text
    • http://baharemadinah.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613e302dca33e---muzekozexutigamikefimix.pdfIn PDF document text
    • https://www.lesson-online.org/wp-content/plugins/super-forms/uploads/php/files/ln6q4534thpr486ftj926r6el3/3832951808.pdfIn PDF document text
    • http://a-pluset.com/userfiles/26706690345.pdfIn PDF document text
    • https://armour-technoz-ca.otzol.net/ckfinder/userfiles/files/tesijejadosodoxisowew.pdfIn PDF document text
    • https://takiminsahada.com/wp-content/plugins/super-forms/uploads/php/files/dlpnsgmrm90lb3a8orbskq862h/joluxoje.pdfIn PDF document text
    • http://botaierpharm.com/upload/files/14883218474.pdfIn PDF document text
    • http://tbff-bygg.se/img/files/22467477020.pdfIn PDF document text
    • http://eko-gospodarstwo.eu/files/file/96983818072.pdfIn PDF document text
    • http://belly.bpv.su/content/files/files/kimunekadidatusomaxaxif.pdfIn PDF document text
    • https://aurorabersinar2.com/contents/files/27940494512.pdfIn PDF document text
    • https://pinkrali.com/calisma2/files/uploads/sopozida.pdfIn PDF document text
    • http://qdjshg.com/files/file/pabapivujalutedusa.pdfIn PDF document text
    • http://www.alex-vasilkov.ru/images/wisdom/file/50878816728.pdfIn PDF document text
    • http://phdpecs.hu/userfiles/files/vasixezasetuvomapatupaf.pdfIn PDF document text
    • https://khmernative-rice.com/userfiles/file/jolofowupirivedadefutaxak.pdfIn PDF document text
    • http://noithatdangcap.vn/app/webroot/uploads/files/65300608359.pdfIn PDF document text
    • https://resttour.com/images/userfiles/files/nonomipisexudes.pdfIn PDF document text
    • http://abwnickersonplaza.com/uploads/files/zejekega.pdfIn PDF document text
    • https://maconlux.ovh/userfiles/files/87704173630.pdfIn PDF document text
    • https://perfecthospital.net/FCKeditor/file/duxogalanenaludogukafano.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/Om9ozkHLxGw/uplcv?utm_term=dead+empire+zombie+war+mod+apkPDF 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_off0000e00a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE00A 18548 bytes
SHA-256: 06cd3ca9fdc9d1dd554e755e5ba2b4bb383d5f58fdc223d96202d2c3cce8e603
font_01_sfnt_off0001109d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1109D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000128b4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x128B4 10516 bytes
SHA-256: f1dd286977032f442e2ffb93029d9c473f25cb3ad6394a9bb9722b549ed54ff2