Malicious PDF — malware analysis report

Static analysis result for SHA-256 8cd4f86f68d15190…

MALICIOUS

PDF

79.8 KB Created: 2021-09-12 10:12:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 2e8ce2dec90e93a37861057817595db4 SHA-1: 2472c56844d87f1eecc0dcbf24b2e20f42ee7120 SHA-256: 8cd4f86f68d15190a4b4dd339ed632ffedca62e66da5ab71ede4641e1ee57824
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external links, with several heuristics indicating it functions as a link farm, potentially directing users to compromised websites or phishing pages. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware delivery. No scripts were extracted, but the PDF structure itself is indicative of a malicious lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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://artistaone.co/userfiles/files/23797690939.pdf In PDF document text
    • http://jezirka-biobazeny.cz/UserFiles/File/migosufelegiv.pdfIn PDF document text
    • http://mibenjamin.com/userfiles/file/vijekiludevaki.pdfIn PDF document text
    • http://www.mtpartnersfl.com/wp-content/plugins/formcraft/file-upload/server/content/files/16132af9e14fc8---90866425729.pdfIn PDF document text
    • http://jrmhandling.nl/upload/file/bukiruli.pdfIn PDF document text
    • http://hightopeducation.com/cms_uploaded/file/18126598974.pdfIn PDF document text
    • http://xetaihyundai.net/upload/files/zakafopodosava.pdfIn PDF document text
    • https://whiteplacard.com/UserFiles/file/39246810006.pdfIn PDF document text
    • https://balbok.net/admin/ckfinder/userfiles/files/tetetugarudumitowewu.pdfIn PDF document text
    • http://gearonlaw.net/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/49565356072.pdfIn PDF document text
    • http://alwaysshine.com/fileimage/file/kiximewuxidifadar.pdfIn PDF document text
    • https://satuldelut.ro/ckfinder/userfiles/files/79089450056.pdfIn PDF document text
    • https://massagetheory.ca/wp-content/plugins/super-forms/uploads/php/files/3a9f33b52d4b07891eeaa7de4097fa0c/49455094324.pdfIn PDF document text
    • http://bdsps.org/slbdavbatala/userfiles/file/85106313622.pdfIn PDF document text
    • https://dienhoanghean.com/upload/ck/files/85289249623.pdfIn PDF document text
    • http://tfe-design.dk/userfiles/file/80567327967.pdfIn PDF document text
    • https://sketchup360.vn/wp-content/plugins/super-forms/uploads/php/files/b5hf6v3fbqi8vmno15spgvcv8v/78191312513.pdfIn PDF document text
    • https://workinhotel.com/upload/fckfile/43190005753.pdfIn PDF document text
    • http://ecosdaliberdade.com/ckfinder/userfiles/files/77414194187.pdfIn PDF document text
    • http://fixafilm.se/userfiles/file/kovosadujojiwobaketo.pdfIn PDF document text
    • http://mail-business.ru/uploads/file/98345943643.pdfIn PDF document text
    • https://barcelonacentremedic.cat/files/galeria/files/futomodofovoj.pdfIn PDF document text
    • http://digilit.ir/basefile/digilitir/files/28825360906.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/zMnd8XtcwSM/uplcv?utm_term=android+tv+remote+ios+appPDF 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_off0000d406.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD406 17616 bytes
SHA-256: c7d848a8d344159a8a5d2357c410e902d478d8fa7ce07f2b67abe1fd189c5efa
font_01_sfnt_off00010183.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10183 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001199a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1199A 10552 bytes
SHA-256: eed60e8cc6c55bac5eae19bac1306697f966ee8684968102d638a7257880d0e8