Malicious PDF — malware analysis report

Static analysis result for SHA-256 5f2bdf2c3efdae75…

MALICIOUS

PDF

86.0 KB Created: 2021-09-13 17:56:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 7870dcd4890de835fb9de8c11fb4ab7e SHA-1: c5391a29869204d9d8b811728942124e53a4728f SHA-256: 5f2bdf2c3efdae758727a80ad597c6e25d71c60280e31e1f01d442d0de678641
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs that form a link farm, a common technique for phishing or distributing malware. Several heuristics indicate the presence of a link farm, with some links pointing to compromised WordPress sites. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://krisoc.ru/uplcv?utm_term=best+android+apps+for+coding PDF link annotation
    • http://td-mg.ru/uploads/files/97155539236.pdfIn PDF document text
    • http://casaperferiesantamariagoretti.com/writable/public/userfiles/file/mopurijo.pdfIn PDF document text
    • http://mariondhuique-mayer.com/data/file/88492173531.pdfIn PDF document text
    • https://braindevelopmentmaps-org.neurondevelopment.org/userfiles/files/woxuneganowanejobomoziwu.pdfIn PDF document text
    • https://udachi.co.th/wp-content/plugins/super-forms/uploads/php/files/rg03oav4o9bna092aqlr2p2bpg/54216436022.pdfIn PDF document text
    • http://urjabatteries.in/userfiles/file/39336498027.pdfIn PDF document text
    • http://montpellier-business-plan.fr/mbp/upload/images/images/upload/ckfinder/37625029775.pdfIn PDF document text
    • http://owv-sad.de/userfiles/files/gatidudape.pdfIn PDF document text
    • http://msslink.ru/userfiles/files/93540501913.pdfIn PDF document text
    • http://www.hptindia.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612ec6e36a344---72152894006.pdfIn PDF document text
    • http://geodavidepini.it/userfiles/files/risajugu.pdfIn PDF document text
    • http://elma-itc.ru/!upload/files/ratodogu.pdfIn PDF document text
    • https://myphi.biz/nbloom/fckuploads/file/40153535453.pdfIn PDF document text
    • http://snookerfootball.eu/wp-content/plugins/formcraft/file-upload/server/content/files/16131aa45ada1b---95264109767.pdfIn PDF document text
    • http://distant-property.ru/fck_editor_files/files/xevepuwotowajop.pdfIn PDF document text
    • http://cimkezes.hu/uploads/ckfinder/userfiles/files/kuxodumuxawibujufasurefo.pdfIn PDF document text
    • https://jcmimoveis.com/userfiles/file/zolika.pdfIn PDF document text
    • http://dieutrimun.myphamkangnam.vn/webroot/img/files/64869029575.pdfIn PDF document text
    • http://vaithun.net/upload/files/wurijurizatesamonuririwe.pdfIn PDF document text
    • https://lotteppta.net/beta/assets/file/75496284176.pdfIn PDF document text
    • http://sciattella.net/images/file/danudijij.pdfIn PDF document text
    • https://transcendenceit.com/wp-content/plugins/super-forms/uploads/php/files/4d3f9da395ee96a72ffdbb9b56516922/1181796424.pdfIn PDF document text
    • 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_off0000ece1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xECE1 17372 bytes
SHA-256: 52158855c63de96627f9e0842c371fa570647b293fbf89c4acbc47d1ee771eb6
font_01_sfnt_off00011993.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11993 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000131aa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x131AA 10804 bytes
SHA-256: 7ba18f0358a08c0be17cdf4327277e1dd79e40baf53e9523ac86555ad8e1eb0b