Malicious PDF — malware analysis report

Static analysis result for SHA-256 20858cc80f2f16d6…

MALICIOUS

PDF

73.5 KB Created: 2021-09-20 09:50:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 7f2d5047ca199b701e5a143c483b8d1f SHA-1: c821fe695149441d33ae73fba0f028dac119791d SHA-256: 20858cc80f2f16d68c3b564ffc88dbcdf374c2e230e786976956edb4d20e4821
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised WordPress upload directories or disposable hosting, indicating a link farm designed to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely involving exploitation of PDF vulnerabilities to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9982

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://garglob.ru/uplcv?utm_term=best+microphone+app+for+android PDF link annotation
    • https://eletmodguru.hu/files/files/dafutoparunuvinizudugixi.pdfIn PDF document text
    • http://e3edu.vn/public/ckfinder/core/connector/php/connector.phppublic/uploadsfiles/tuzam.pdfIn PDF document text
    • http://ellissi.org/userfiles/files/wenudod.pdfIn PDF document text
    • https://holocaustresearch.pl/nowy/photo/file/roridamuvimuju.pdfIn PDF document text
    • https://www.booster-p.com/wp-content/plugins/formcraft/file-upload/server/content/files/16138df28437ee---nogutid.pdfIn PDF document text
    • http://pmdrecycling.com/wp-content/plugins/formcraft/file-upload/server/content/files/161409ec594a98---pewiwiwoputunekozof.pdfIn PDF document text
    • http://4998horo.gmmwireless.com/contents/files/jabone.pdfIn PDF document text
    • http://tucsokszekszard.hu/images/news/file/kemigufuja.pdfIn PDF document text
    • http://brcassociati.com/userfiles/files/10888135660.pdfIn PDF document text
    • https://successstudio.net/userfiles/file/12395382574.pdfIn PDF document text
    • http://kemnhapkhau.com/upload/files/rutuzakugojaxogejajosigek.pdfIn PDF document text
    • https://academiesutherland.com/userfiles/file/fopaxasupajidigufixul.pdfIn PDF document text
    • https://gamletaarnhuset.no/wp-content/plugins/formcraft/file-upload/server/content/files/161353e703ac59---pizuwiwapose.pdfIn PDF document text
    • https://vickers-electronics.co.uk/wp-content/plugins/super-forms/uploads/php/files/fca247d4a22e0169eccfce8fdd56244a/69135764125.pdfIn PDF document text
    • https://crownprolaw.com/userfiles/Proj_Name/files/dedamuzikejus.pdfIn PDF document text
    • http://eastendmediation.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/rixemogakiguniwekoviki.pdfIn PDF document text
    • http://www.airportlimofortlauderdale.net/wp-content/plugins/formcraft/file-upload/server/content/files/1612e987a26fdf---bitadok.pdfIn PDF document text
    • http://nfc-lampang.com/user_img/files/61279118743.pdfIn PDF document text
    • https://marwaautorepair.com/nbloom/fckuploads/file/87339100266.pdfIn PDF document text
    • http://vdgairconditioning.nl/wp-content/plugins/formcraft/file-upload/server/content/files/161464be170d3b---86162332917.pdfIn PDF document text
    • https://binarbaidequipment.com/public_html/userfiles/file/bokukulekinijixozigu.pdfIn PDF document text
    • http://deurwater.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613c0a57808f6---65750097370.pdfIn PDF document text
    • http://www.onegelha.com/wp-content/plugins/super-forms/uploads/php/files/098c870cc8b3f95641bc50e598647791/57407369550.pdfIn PDF document text
    • http://booklandbooks.com/userfiles/file/xewazedikulinururigufon.pdfIn PDF document text
    • https://drosamahetta.com/userfiles/file/rireganimosoburisudefat.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_off0000bd0a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBD0A 16212 bytes
SHA-256: 14bb5a08f365b74ba8dca48b47e83272bf25bf5dc4953996f18d613cb5a2b1f3
font_01_sfnt_off0000e6bb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE6BB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000fed2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFED2 10892 bytes
SHA-256: cb4f4c5bc6aff248bfd9c7929e9cf7e289d2204131131cdabdda3ee84b900f5c