Malicious PDF — malware analysis report

Static analysis result for SHA-256 6df1f21636a1df80…

MALICIOUS

PDF

78.7 KB Created: 2021-09-13 12:34:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-21
MD5: f7da8122b60e81954441a99659c6b33f SHA-1: 59dd4a464a202911b7a2207c71e8ff6184ac2bf8 SHA-256: 6df1f21636a1df8098d1d4f1e2e3fcafeed6f5e63c135c75448eb07771eb38ae
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites or disposable hosting, indicating a link farm designed to lure users to malicious destinations. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware delivery. No scripts were extracted, and the document body was unreadable, but the heuristic firings and URL analysis are sufficient to determine the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9968

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 http://motocams.cz/ckfinder/userfiles/files/32081537901.pdf In PDF document text
    • http://drprdesaihospital.com/uploads/85915592237.pdfIn PDF document text
    • http://lnv-cnc.gr/userfiles/file/jeparuxaponixololaxi.pdfIn PDF document text
    • http://wmsone.com/eimages/file/29067241372.pdfIn PDF document text
    • http://rockbond-aac.com/id-admin/fckImages/file/xokugiladipudoteza.pdfIn PDF document text
    • http://brenna-ski.pl/userfiles/file/75407271019.pdfIn PDF document text
    • https://goldfieldssanddrags.com.au/ckfinder/userfiles/files/padebogamezotemaf.pdfIn PDF document text
    • https://stcatherine.ac.ug/wp-content/plugins/formcraft/file-upload/server/content/files/1613016d388013---31312452259.pdfIn PDF document text
    • http://dsraxys.com/uploads/wadunemomepe.pdfIn PDF document text
    • https://mosoptagro.ru/wp-content/plugins/super-forms/uploads/php/files/5525f09720059dc0dbcbdf5cd4b9f88c/kovibuj.pdfIn PDF document text
    • https://indicaperu.com/userfiles/file/32812229850.pdfIn PDF document text
    • http://imcborivali.org/userfiles/file/xaraxewigubajubapijibak.pdfIn PDF document text
    • https://yesilkoyluleriz.biz/resimler/files/35385565583.pdfIn PDF document text
    • https://goldenparadisestsimons.com/wp-content/plugins/super-forms/uploads/php/files/a17e1b44b6ca826ac2f43ff807ea4387/28336567379.pdfIn PDF document text
    • https://www.benkorner.nl/admin/library/ckfinder/userfiles/files/rijixajeduxex.pdfIn PDF document text
    • http://fslawoffice.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/18528672742.pdfIn PDF document text
    • https://aaaxxion.info/images/file/talazevavunuvigoxarose.pdfIn PDF document text
    • http://teakdeck.pl/files/file/zutozigedemo.pdfIn PDF document text
    • http://lapenya.cat/imgjovesnaves/file/nitekumamimana.pdfIn PDF document text
    • https://km2804.com/ckupload/files/59401435228.pdfIn PDF document text
    • https://www.moxiclear.com.au/application/third_party/ckfinder/userfiles/files/xeputebuwupamuvepeni.pdfIn PDF document text
    • http://finproekt-msk.ru/userfiles/file/voxigidavetu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BkSY9tpko7c/uplcv?utm_term=tab+button+androidPDF 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_off0000ca83.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCA83 19844 bytes
SHA-256: a9aea65fb4e15e48bb323ff17e40d3e5d3d7c44444f6886f20abb1990edfa5d8
font_01_sfnt_off0000febb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFEBB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000116d2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x116D2 10100 bytes
SHA-256: 210345e5ef7b6be7da6c7e1cc7c899ada3c74350efbeb54372cac3f8b867e6d0