Malicious PDF — malware analysis report

Static analysis result for SHA-256 8a9e4d76430b0efe…

MALICIOUS

PDF

77.4 KB Created: 2021-09-01 04:51:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-22
MD5: c347862b89d02868237335ea4776e928 SHA-1: e4d1d42d12846b7925cf242a3bd0c21a311b0138 SHA-256: 8a9e4d76430b0efe64bd864ba33952c5575c1479cf68513f743f8fd063fde413
156 Risk Score

Malware Insights

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

The PDF contains a link farm directing users to multiple external URLs, with several hosted on compromised CMS platforms. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to phish or deliver further malware. The primary attack pattern involves luring users to external sites via a malicious attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9901

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://suttonoakfarms.com/clients/880813/File/45806936497.pdf In PDF document text
    • https://cupanghitam.com/contents//files/80314185799.pdfIn PDF document text
    • https://patriot.ch/wp-content/plugins/super-forms/uploads/php/files/c8ut24idt3073oa25i42klkrr0/49432317081.pdfIn PDF document text
    • http://viermaalh.nl/Bottesteyn/Site/afbeeldingen/file/guxegigekuloniwuwiwenonal.pdfIn PDF document text
    • http://www.pranabkumar.com/fckimages/file/72747314294.pdfIn PDF document text
    • https://doanandieuduong295doson.vn/namthuan/images/news/files/mikonuwiwepuku.pdfIn PDF document text
    • https://eurotechcorp.vn/admin/webroot/upload/image/files/23944766061.pdfIn PDF document text
    • http://szguilong.com/userfiles/files/tojiropolonulefe.pdfIn PDF document text
    • http://math-talk.kr/wp-content/plugins/super-forms/uploads/php/files/hm91162r0sb7oastvbqamjge25/59251967762.pdfIn PDF document text
    • http://studiomarcheluzzo.it/userfiles/files/75813803944.pdfIn PDF document text
    • http://www.ebsjosepirosamaria.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f388075ce50---nebaluxux.pdfIn PDF document text
    • https://mvpartners.be/images/uploadedimages/file/mujutuniwisuruteluno.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16082c267aab36---57378203065.pdfIn PDF document text
    • https://daiichitravel.com/uploads/news_file/zuwuf.pdfIn PDF document text
    • https://krossi.ru/images/content/files/18329874784.pdfIn PDF document text
    • http://www.louthadventures.ie/wp-content/plugins/formcraft/file-upload/server/content/files/1609080df99a86---49283353101.pdfIn PDF document text
    • http://delannahotel.com/user_img/file/30077592384.pdfIn PDF document text
    • https://edu-mate.kr/_UploadFile/Images/file/14446237471.pdfIn PDF document text
    • http://fygl.net/uploads/file/201750194537.pdfIn PDF document text
    • http://papinchess.ru/userfiles/file/71328408636.pdfIn PDF document text
    • https://www.jahnigterbraak.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1608421f74beb7---gawum.pdfIn PDF document text
    • https://master.plus/wp-content/plugins/super-forms/uploads/php/files/585378170ff4795ec2059e2ffd55ffc2/lufizitonodoburaxodeveve.pdfIn PDF document text
    • https://digireg.at/upload/66457554485.pdfIn PDF document text
    • https://asiatravel.kg/wp-content/plugins/super-forms/uploads/php/files/39de81bd6351e54edb08f209cdd9d122/tipawokitiroreru.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609089588ffe4---nugovobegunokawasadat.pdfIn PDF document text
    • https://kueapem.com/contents//files/57289957289.pdfIn PDF document text
    • http://dongamold.com/fckeditor/upload_files/file/46259775099.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/cv9VXjIrmdE/uplcv?utm_term=the+best+of+penthouse+forumPDF 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_off0000cb4e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCB4E 17400 bytes
SHA-256: 20969a3fa32d1ea41737bcc4cc3e8ca3a3e21976a3d164eb1405a6e820e5fbe3
font_01_sfnt_off0000f7fa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF7FA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011011.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11011 10524 bytes
SHA-256: 4c924236d72f52be88339de31090b75c80eabebdef8069a812c8a6a786c8965e