Malicious PDF — malware analysis report

Static analysis result for SHA-256 7936ace37977f187…

MALICIOUS

PDF

106.4 KB Created: 2021-07-06 15:58:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-25
MD5: 73166171d48b9eae311cffa1ef904ccc SHA-1: 1b7cfebd9199f0e7af03c14e29fd762d280ed8b9 SHA-256: 7936ace37977f187ba4d8dd3ec2fe16ca23540fded29c105b1bb510ebe6f9131
156 Risk Score

Malware Insights

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

The PDF contains a large number of links, many of which point to compromised WordPress sites. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution. The document body is heavily obfuscated and does not provide clear textual lures, but the structure and URL analysis are sufficient to infer a malicious link farm.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9790

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://akbmodel.com/wp-content/plugins/formcraft/file-upload/server/content/files/16079dd1bd0a8a---jojevinovazodugusonav.pdf In PDF document text
    • https://www.ayersworthglen.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607e72ca6b251---42202295692.pdfIn PDF document text
    • https://lakecountyoralsurgery.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608340ec11873---kimafezafefaxapopalobi.pdfIn PDF document text
    • http://itaindustrial.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160bbbd5000567---24744545269.pdfIn PDF document text
    • http://icltindia.in/userfiles/file/3940011584.pdfIn PDF document text
    • https://villadorottya.hu/uploads/frontend/files/29469657619.pdfIn PDF document text
    • http://bergfin.se/wp-content/plugins/formcraft/file-upload/server/content/files/1607829521c045---benoruwozu.pdfIn PDF document text
    • https://thewentworthco.com/wp-content/plugins/super-forms/uploads/php/files/skmmt6gojnud05bl7dc754s4df/zofud.pdfIn PDF document text
    • http://kotolantopeni.cz/file/86297682231.pdfIn PDF document text
    • https://www.qbuildsoftware.com/wp-content/plugins/super-forms/uploads/php/files/450343c31eaaf71f8d494d0944c3f384/74442314792.pdfIn PDF document text
    • https://www.baptistenhardenberg.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16086e07f6b7ba---34575346372.pdfIn PDF document text
    • https://gulfsupremesa.com/ckfinder/userfiles/files/9052723415.pdfIn PDF document text
    • http://daimarconstrucciones.com/images/admin/file/fitura.pdfIn PDF document text
    • http://alituncer.com/userfiles/file/zafupumeradenofarim.pdfIn PDF document text
    • http://apcmagon.com/userfiles/nenifekafonaruj.pdfIn PDF document text
    • https://nisahanpin.com/calisma2/files/uploads/22971838451.pdfIn PDF document text
    • https://www.budgetskemaet.dk/wp-content/plugins/formcraft/file-upload/server/content/files/1609ed7a6b7d64---25043404629.pdfIn PDF document text
    • https://traffictkt.com/viking1/uploads/files/nirerifedosalo.pdfIn PDF document text
    • http://www.majbrno.cz/uploads/files/56400211829.pdfIn PDF document text
    • https://proff-doors.ru/wp-content/plugins/super-forms/uploads/php/files/c309c1d10c3a0d2254ca88a4fb790eee/jelibodozotipodanezo.pdfIn PDF document text
    • http://www.virtualaid.eu/wp-content/plugins/formcraft/file-upload/server/content/files/1606d8aedf0fb3---58286642967.pdfIn PDF document text
    • https://www.conkite.com/wp-content/plugins/super-forms/uploads/php/files/c27ff362544189f009f1d0f9ebe50682/jexutiwonu.pdfIn PDF document text
    • https://refundsrefunds.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607c0db47e7f4---gidukufa.pdfIn PDF document text
    • https://doitsolutions.co/wp-content/plugins/super-forms/uploads/php/files/b6ac0264d97f319c10d056469b12fd4e/zamutaguxonilejatajera.pdfIn PDF document text
    • http://burmeseburmilla-allevamento.com/userfiles/files/luzuvasopilemizetabasivo.pdfIn PDF document text
    • https://www.cr-sdc.org/wp-content/plugins/super-forms/uploads/php/files/09b79517c854902c41b2c179ac6b3fb6/8189898249.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3vuEKuznOb8/uplcv?utm_term=operational+research+book+pdfPDF 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_off00013c4b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13C4B 18132 bytes
SHA-256: cc5504d6a07edc6183c0b864a2eeed056617330a16f97efae8a896a8c198689b
font_01_sfnt_off00016ac9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16AC9 10972 bytes
SHA-256: 8bb820d05d5356d5952c2d652a91bc3455087df285c7de1984510a5fa588be8e
font_02_sfnt_off000183f9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x183F9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1