Malicious PDF — malware analysis report

Static analysis result for SHA-256 c9f0788962331581…

MALICIOUS

PDF

72.1 KB Created: 2021-09-23 08:05:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: f8c5918edda4ba5d9e3efacbf198feab SHA-1: b9f506d03df57f0fa19e775150b437a7571812b5 SHA-256: c9f078896233158125aa26c809b1b6473ea5d15f97eea3735bb752a98f3cf421
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to compromised WordPress sites, suggesting a link farm designed to redirect users to malicious content. The ClamAV detection and ML classifier strongly indicate malicious intent, likely phishing or malware delivery. The document body is heavily obfuscated and unreadable, providing no direct clues to its purpose beyond what the heuristics reveal.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9984

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://orkhaconstruction.com/wp-content/plugins/super-forms/uploads/php/files/0pik2co5m3dl87m1593dqph23n/31277848745.pdf In PDF document text
    • http://zensushialiso.com/uploads/files/24683604777.pdfIn PDF document text
    • https://bettenbaehren.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613a3bde35a20---kulovumojuwulex.pdfIn PDF document text
    • http://kargiskola.ge/myadmin/ckeditor/ckfinder/userfiles/files/logidekobagutemoteg.pdfIn PDF document text
    • https://laneopx.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614395ae33ce4---19891256501.pdfIn PDF document text
    • https://specializedfacilitymgt.com/public_html/userfiles/file/pidumodafovafawodegireka.pdfIn PDF document text
    • https://ctapigroup3.com/contents/files/18014209902.pdfIn PDF document text
    • https://abctranslink.com/ckfinder/userfiles/files/sunimenixufeselezefofewem.pdfIn PDF document text
    • https://nordavril.com/userfiles/file/fufexugodatakomigol.pdfIn PDF document text
    • http://argol-editions.fr/userfiles/file/nivenalizebenit.pdfIn PDF document text
    • http://x-mobio.com/upload/files/9107381038.pdfIn PDF document text
    • https://designmaster.in/scgtest/eec-new/codelibrary/ckeditor/ckfinder/userfiles/files/23299839076.pdfIn PDF document text
    • https://jordanadams.com/ckfinder/userfiles/files/sexuvoxewesavirep.pdfIn PDF document text
    • http://kbo.pl/ckfinder/userfiles/files/10912442174.pdfIn PDF document text
    • http://ourconn.com/userfiles/file/202109150617151226.pdfIn PDF document text
    • http://theemasternetworker.com/ckfinder/userfiles/files/zaxukobikisawododig.pdfIn PDF document text
    • http://architettorobertafasola.eu/userfiles/files/23994508791.pdfIn PDF document text
    • http://rc-mst.com/mst/_upload/files/wexuderonofavikebaxevoroj.pdfIn PDF document text
    • http://hsi-international.com/ckfinder/userfiles/files/19955994734.pdfIn PDF document text
    • https://tonymusic.se/UserFiles/files/64587446482.pdfIn PDF document text
    • http://kaies.net/upfiles/210910165407755392ob05it.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/6naE_Nh8_CY/uplcv?utm_term=five+nights+at+freddy%27s+unblocked+2PDF 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_off0000b5af.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB5AF 11400 bytes
SHA-256: d6dce13399b41799effde0786a3b4c2c92516b637b8f53f40306f88a7a0cf6ba
font_01_sfnt_off0000d067.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD067 16416 bytes
SHA-256: 26d6f3417c963ba33ad5fb807f31bd7e8f894538df0397f002ddbd54ae4775d8
font_02_sfnt_off0000fa8e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA8E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1