Malicious PDF — malware analysis report

Static analysis result for SHA-256 3b81b4364d7a2b29…

MALICIOUS

PDF

91.1 KB Created: 2021-08-04 21:44:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-02
MD5: 6f2e1064ec558e3f29dc67df5e0ec3e5 SHA-1: f711875f3083090f5db9deccc116eb7873cebb0e SHA-256: 3b81b4364d7a2b296db0a32f3e535d775a948510df22fc0ce725c6da7b606f44
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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://nbc.ua/design/pic/file/45862768624.pdf In PDF document text
    • https://divinesacredshakti.com/wp-content/plugins/super-forms/uploads/php/files/bcb2b07c05d2af8918e9f3384130c632/55649585454.pdfIn PDF document text
    • https://www.kunapak.com/wp-content/plugins/super-forms/uploads/php/files/8iv9au0ivn25f1n0c6rtlerldv/47980542425.pdfIn PDF document text
    • http://zonwering-belgie.eu/ckfinder/userfiles/files/luninadorinumaberabuzut.pdfIn PDF document text
    • http://bjoybrands.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609c8bcd8c15a---juripanuz.pdfIn PDF document text
    • http://aexpress.lv/index/images/up/file/74687802617.pdfIn PDF document text
    • https://performanshost.com/calisma2/files/uploads/badamumaxa.pdfIn PDF document text
    • http://www.christinemartin.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160aa4b45461a7---rusuzazolijaguji.pdfIn PDF document text
    • https://hansenlight.com/UploadFile/files/lemapafip.pdfIn PDF document text
    • http://multi-accueil.fr/ressource/site-image/files/68363630744.pdfIn PDF document text
    • http://mfplus.ba/wp-content/plugins/formcraft/file-upload/server/content/files/160a4ff7419fed---zisiw.pdfIn PDF document text
    • https://djhelaly.com/wp-content/plugins/super-forms/uploads/php/files/76fd3d156c447dd2f70ad2f726439c91/bowodubaburasi.pdfIn PDF document text
    • https://unitedcardsolutions.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f5cbe5940e1---26054338559.pdfIn PDF document text
    • https://law.myvzl.com/wp-content/plugins/super-forms/uploads/php/files/jgih2du19745ilt81644orhnop/51435496177.pdfIn PDF document text
    • https://bandai-k.com/userfiles/file/miwuvovodinula.pdfIn PDF document text
    • https://noddy.nu/images/file/xusuvevijosimiz.pdfIn PDF document text
    • https://newat.ru/wp-content/plugins/super-forms/uploads/php/files/a909fc7cef2eaf0654e73d4e56236f8c/38260508604.pdfIn PDF document text
    • https://gulertrafik.com/wp-content/plugins/super-forms/uploads/php/files/qnvm0q6763kgv42ov4tk0deii2/41656705528.pdfIn PDF document text
    • https://barrierball.cl/ckfinder/userfiles/files/24932640033.pdfIn PDF document text
    • http://hncastlecable.com/d/files/wetupewokono.pdfIn PDF document text
    • https://ascinfratech.com/clientprojects/trading/file/jileraxemewez.pdfIn PDF document text
    • http://www.melloecastro.com/wp-content/plugins/formcraft/file-upload/server/content/files/160722ee53d35c---wenevejukutiwan.pdfIn PDF document text
    • https://cplastik.com/data/cms/file/97164565457.pdfIn PDF document text
    • https://www.bouwenaaneensterkwerkgeversmerk.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1607140d852487---volulafi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/6naE_Nh8_CY/uplcv?utm_term=how+to+study+for+dc+learners+permit+testPDF 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_off0000feac.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFEAC 11072 bytes
SHA-256: 42fbcebbf92f6f82dc5f8e517ec14c644254060bf33c35e17662d0081d5a6e4b
font_01_sfnt_off00011885.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11885 17664 bytes
SHA-256: 9cb4b87e3140a9115c153d2fc5d39d625bb381dffef485af0a8025131fbf3850
font_02_sfnt_off000146ab.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x146AB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1