Malicious PDF — malware analysis report

Static analysis result for SHA-256 e3936d3d8509d421…

MALICIOUS

PDF

73.8 KB Created: 2021-10-01 00:24:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: b747b2fe64c4c7813fe44bf60d5f20ac SHA-1: 4c4cb0e8a5a77a549a7542f846c85680219b4bd9 SHA-256: e3936d3d8509d421839c78ab08dbc380c7e83843f917a896f5ed7a01783db8f6
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external links, many pointing to compromised CMS uploads or disposable hosting, suggesting a link farm designed to redirect users. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. Although no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with malicious PDF lures.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://queure.ru/uplcv?utm_term=roald+dahl+books+in+sinhala+pdf PDF link annotation
    • https://vili-al.com/uploads/wysiwyg/files/20906328952.pdfIn PDF document text
    • https://husvagnsexpo.se/wp-content/plugins/formcraft/file-upload/server/content/files/1614c0e75ee0a1---24980395866.pdfIn PDF document text
    • https://carmelocuritiba.com.br/ckfinder/userfiles/files/19156971009.pdfIn PDF document text
    • http://debsecond.net/UserFiles/File/78366211040.pdfIn PDF document text
    • https://tarzminder.com/resimler/files/lekijoxes.pdfIn PDF document text
    • http://www.gdchgs.com/admin/img/files/fuwiliv.pdfIn PDF document text
    • http://kursverwaltung.fit-n-essen.ch/ckfinder/userfiles/files/39940281238.pdfIn PDF document text
    • https://www.playitdirect.ca/ckfinder/uploadfiles/files/disafowefurogukuwulas.pdfIn PDF document text
    • https://celovechurch.org/wp-content/plugins/super-forms/uploads/php/files/83ec5d0c2b68b357f2d8a78bd7372205/91142109209.pdfIn PDF document text
    • http://verkoop-je-wagen.be/wp-content/plugins/formcraft/file-upload/server/content/files/16152ad2009e6b---7848088966.pdfIn PDF document text
    • https://onutglen.com/caningest/images/file/pirefabon.pdfIn PDF document text
    • http://gucaoyun.com/uploads/file/200256275472.pdfIn PDF document text
    • https://tiemhoamo.com/data/dulieu/files/88055805746.pdfIn PDF document text
    • https://rockeit.com/userfiles/file/jememijexenubedidovebo.pdfIn PDF document text
    • https://manpowernepal.net/ckfinder/userfiles/files/94752861853.pdfIn PDF document text
    • http://fuhua.tumujike.com/assets/upload/files/202109260019316082.pdfIn PDF document text
    • https://cambodiadriverservice.com/userfiles/file/tubemukog.pdfIn PDF document text
    • http://salonorganica.ru/upload/files/17149643835.pdfIn PDF document text
    • https://weeb.nu/userfiles/file/73634960292.pdfIn PDF document text
    • http://prakseologia.eu/userfiles/file/13270615893.pdfIn PDF document text
    • http://tasarimak.com/ckfinder/userfiles/files/nurajosowolomeriromazi.pdfIn PDF document text
    • https://skvacations.com/userfiles/file/pekij.pdfIn PDF document text
    • http://pnktools-th.org/ckfinder/userfiles/files/zobesositamugisesalu.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_off0000b5de.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB5DE 19316 bytes
SHA-256: 9358bcd68cbad3b3d59088dc2690e87f6b00869547d471eddaa633dd8b4ebf0c
font_01_sfnt_off0000e8ae.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE8AE 10540 bytes
SHA-256: 034c1694cc4a8d565b57258cd1348b8667888cdd70af52dd28bc322aa41a20ee
font_02_sfnt_off00010055.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10055 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1