Malicious PDF — malware analysis report

Static analysis result for SHA-256 16c352fd801c1ed6…

MALICIOUS

PDF

79.8 KB Created: 2021-06-29 20:21:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-20
MD5: d7a21c4c3be11d6c301140309b88d617 SHA-1: 0afc9f837b6903f9fa2f68b5878b34ed8f11be45 SHA-256: 16c352fd801c1ed686f2d139ac31913d82db45ba9989d64e33806fa5fe396f83
156 Risk Score

Malware Insights

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

The PDF contains numerous links to compromised WordPress sites, indicating a link farm designed to redirect users to potentially malicious content. ClamAV detection and ML classification strongly suggest this PDF is malicious, likely serving as a lure for phishing or malware downloads. No scripts were extracted, but the extensive use of compromised upload paths points to a distribution mechanism.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9949

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://www.orhancoskun.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a05256edc89---19608172329.pdf In PDF document text
    • https://legacydockandmarine.com/wp-content/plugins/super-forms/uploads/php/files/007609275262382c4d8d0cb6ea9dae76/botuxi.pdfIn PDF document text
    • http://china-hold.com/UploadFile/file/20210529205239009.pdfIn PDF document text
    • https://33mobility.net/uploads/files/41281458605.pdfIn PDF document text
    • http://www.kissdocs.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160b60851cc7cd---tonexusekitavoxotuwado.pdfIn PDF document text
    • http://www.rlktechniek.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16077c78ec0ace---wipizazejezo.pdfIn PDF document text
    • http://wenxuezj.com/images/File/74450745165.pdfIn PDF document text
    • http://ehs1958.org/clients/73155/File/xajumupakijarirogibasem.pdfIn PDF document text
    • https://wsbtitan.com/images/file/70632654812.pdfIn PDF document text
    • https://leicht-spb.ru/wp-content/plugins/super-forms/uploads/php/files/18dea8a5ff9cafe629a6bdfcacd7f625/zemuwin.pdfIn PDF document text
    • https://anthonygillant.com/userfiles/file/32986335263.pdfIn PDF document text
    • https://www.webhisto.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160a25e0d773f1---83156017315.pdfIn PDF document text
    • https://technok.cz/wp-content/plugins/super-forms/uploads/php/files/911a0896ddd6e0634403b03d6c440c5f/bodajafekitiv.pdfIn PDF document text
    • https://a2designbg.com/userfiles/file/lawew.pdfIn PDF document text
    • https://ifacemount.com/wp-content/plugins/super-forms/uploads/php/files/cch9k637616foemcm356e2k01c/92253557378.pdfIn PDF document text
    • https://glbtrader.com/userfiles/file/60418201333.pdfIn PDF document text
    • https://unicornproduction.gr/wp-content/plugins/super-forms/uploads/php/files/4f928c5cef5699fc370e53d0bdc77a57/99264137104.pdfIn PDF document text
    • http://maidnheaven.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d3cc59abe5---44215143910.pdfIn PDF document text
    • http://rentbucharest.net/images/userfiles/93895135450.pdfIn PDF document text
    • https://prtl.pl/userfiles/file/48413988874.pdfIn PDF document text
    • http://hotararicedo.ro/files/files/pupagekufe.pdfIn PDF document text
    • https://cargotavio.ru/files/file/detekutenogekutudinolabu.pdfIn PDF document text
    • http://www.aadhar-interior.com/userfiles/file/7689963814.pdfIn PDF document text
    • http://firewheels.pe/userfiles/file/kozarupopaja.pdfIn PDF document text
    • https://kisikana.hr/userfiles/file/vilixo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/fzgW7-mxBc0/uplcv?utm_term=closest+building+supplyPDF 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_off0000d43e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD43E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ec55.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC55 10692 bytes
SHA-256: b5515f878a27a31986ad75e663f74fe7da32d0cf590eb5fae3cc0957f80c3fdc
font_02_sfnt_off0001048e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1048E 17552 bytes
SHA-256: 5e82e69fe7ce458025c5781fe0f1af62c4eda7aaebfa1b01f2213cedb7fcc8db