Malicious PDF — malware analysis report

Static analysis result for SHA-256 3d5ff389607d4612…

MALICIOUS

PDF

79.9 KB Created: 2021-09-18 07:59:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: da93623fbe338ba476d563e1a4cab636 SHA-1: bf177c358cd8f5c4e2ea204e4ed4c208b9bcd7e5 SHA-256: 3d5ff389607d4612ebc7d5b8b9f2cd98913aa8e9c32ffce1823a96f1f8c96029
156 Risk Score

Malware Insights

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

The file is a PDF containing numerous embedded URLs, many of which point to compromised websites. Heuristics indicate it functions as a link farm, likely intended to lure users to phishing sites or download further malicious content. The ML classifier and ClamAV detection strongly support its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://synerhu.ru/uplcv?utm_term=masalah+autentikasi+wifi+di+android PDF link annotation
    • http://www.grundys.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1613a208860589---lavob.pdfIn PDF document text
    • https://wcdt.co.th/wp-content/plugins/super-forms/uploads/php/files/blhof9r4a904g4pih1g9ok0flc/fabetaturuxubu.pdfIn PDF document text
    • http://mikomisushiwc.com/uploads/files/wozamabefupusuvufazu.pdfIn PDF document text
    • http://arcenevents.nl/site/upload/files/4373700629.pdfIn PDF document text
    • http://gtlfuelmarine.com/userfiles/file/88154839750.pdfIn PDF document text
    • https://dadesigning.com/daduserfiles/files/46653584800.pdfIn PDF document text
    • http://donghotam.com/luutru/files/98594744769.pdfIn PDF document text
    • https://groupunsur1.com/contents/files/61559890256.pdfIn PDF document text
    • http://solamsys.com/userData/board/file/lamur.pdfIn PDF document text
    • https://advicezone.org.uk/wp-content/plugins/super-forms/uploads/php/files/6vu06falct0a80o92dm2dkg1qj/serixajedoroxelo.pdfIn PDF document text
    • https://snowcat.pl/admin/ckfinder/userfiles/files/46240341972.pdfIn PDF document text
    • http://jagodkaprzedszkole.pl/userfiles/file/sakatir.pdfIn PDF document text
    • http://biznesfishki.ru/files/userfiles/files/vigemikevupipoveko.pdfIn PDF document text
    • https://argekaucuk.com/nbg/upload/files/31150433888.pdfIn PDF document text
    • https://webhostmurah.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614176e23fa61---moralujobexukogevupokezes.pdfIn PDF document text
    • http://delannahotel.com/user_img/file/dujiwufebisopifofebev.pdfIn PDF document text
    • http://haai.org/upload/file/84503993131.pdfIn PDF document text
    • http://car-zone.sk/data/data/file/ripaxo.pdfIn PDF document text
    • http://magogaralbamoble.com/galeria/files/rusogagafi.pdfIn PDF document text
    • http://krupongs.com/images/file/fegavikawasupanipurege.pdfIn PDF document text
    • http://darec.sk/files/files/86683376878.pdfIn PDF document text
    • http://terezmisszio.eu/files/file/kopibe.pdfIn PDF document text
    • https://reparationmobile.net/userfiles/file/93351056914.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_off0000d411.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD411 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ec23.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC23 17532 bytes
SHA-256: 666a984f24bbf3ef2216c388d6fc6891e529c1aff3f8970d7bbe9e8c2d85feeb
font_02_sfnt_off000118e2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x118E2 10724 bytes
SHA-256: 42b457a275bf0672e5bdd07ba6cc13bc88cbe03883e72a2abea259b8755857f2