Malicious PDF — malware analysis report

Static analysis result for SHA-256 6f4ebc3fc73f6066…

MALICIOUS

PDF

75.8 KB Created: 2021-09-17 16:44:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: c8c2dd050c7752c1fa51f5e95ed7b14a SHA-1: d4f618be8d45903fd7d622c1a26ea57452b5228c SHA-256: 6f4ebc3fc73f6066437120a3c3ca001e80fc61af8aa76b6c79ab027d028e0e1d
156 Risk Score

Malware Insights

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

The PDF was flagged by ML classifiers and ClamAV as malicious, with heuristics indicating it functions as a link farm. Multiple URLs point to compromised CMS upload storage, suggesting an attempt to lure users to malicious sites. The document body is unreadable, but the presence of numerous links on potentially compromised domains strongly indicates a phishing or malware distribution vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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://bocion.com/ckfinder/userfiles/files/vufafasigozosilugisabujav.pdf In PDF document text
    • http://bassbasement.org/userfiles/file/1941607513.pdfIn PDF document text
    • https://beaufortbond.com/wp-content/plugins/super-forms/uploads/php/files/338d08959dcadd8859fdc42ecaa3581f/1772402544.pdfIn PDF document text
    • http://modelseafarm.com/kweb/ckfinder/userfiles/files/29213857134.pdfIn PDF document text
    • http://letdentalab.com/img/files/38617903427.pdfIn PDF document text
    • http://expertsystemgroup.com/file_media/file_image/file/mowaxokileniberu.pdfIn PDF document text
    • http://avs-market.ru/admin/ckfinder/userfiles/files/56456992847.pdfIn PDF document text
    • http://hueide.com/upload/files/82771861971.pdfIn PDF document text
    • http://tongrentangthai.com/UserFiles/file/64531758529.pdfIn PDF document text
    • https://feniks9.ru/ckfinder/userfiles/files/10240123168.pdfIn PDF document text
    • https://clinicscrm.com/img/files/piramufupabesumoju.pdfIn PDF document text
    • https://nstoplana.rs/ckfinder/userfiles/files/molozamufajobubadux.pdfIn PDF document text
    • https://www.ogblfrontaliers.fr/wp-content/plugins/super-forms/uploads/php/files/aqeh9d0m5aid9eh1bvap4kqfcd/1443288701.pdfIn PDF document text
    • http://www.icodar.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614287d6cfa6c---fodiwalibewuwuwabubojof.pdfIn PDF document text
    • http://mylodge-naoshima.com/tagesogulanu.pdfIn PDF document text
    • https://beaszemin.com/files/wetudisawurejoxawor.pdfIn PDF document text
    • https://confeccionesruiz.cl/UserFiles/File/xunigunojup.pdfIn PDF document text
    • https://dangeloremodeling.com/nbloom/fckuploads/file/45276265302.pdfIn PDF document text
    • http://kolbiko.com/images/uploads/file/86876627607.pdfIn PDF document text
    • http://sevenseahotel.com/uploads/images/files/14365874979.pdfIn PDF document text
    • http://papaicountrylodge-longstay.com/user_img/files/pexafus.pdfIn PDF document text
    • http://ngoinvest.com/uploads/ckfinder/files/ludizonokotabodapob.pdfIn PDF document text
    • http://parateam.cz/file/zobonef.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/FevRqgeaUVY/uplcv?utm_term=free+tropical+wallpaper+for+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_off0000c353.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC353 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000db65.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB65 17828 bytes
SHA-256: 10c316cf1bc5a7a04d6ef76523955a2473958ed972ba962abd7bc7113711338a
font_02_sfnt_off00010971.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10971 10508 bytes
SHA-256: b1c3fd3fd925324658e45e8e68a6cd1a91853fb32ed1c53d7230f2e3a0c5d680