Malicious PDF — malware analysis report

Static analysis result for SHA-256 8ea18c0bdc3a78e9…

MALICIOUS

PDF

83.2 KB Created: 2021-09-07 17:21:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-04
MD5: 9fcc450069b35aa9db0dfe85be4856af SHA-1: 5cffd4eeec0a6a9fefbdda059b5b7ecebcd3c620 SHA-256: 8ea18c0bdc3a78e97831bc908213cacd5fe70fe84b8597b0ce43883fc3762066
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 0.9993

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://vaytieudungtragop.com.vn/wp-content/plugins/super-forms/uploads/php/files/6igtkuco3jb080o2ltgg3klmfl/69969549713.pdf In PDF document text
    • http://www.grupohk.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1606e909f3064f---pogubipikujimuvu.pdfIn PDF document text
    • http://dh-cell.com/ckfinder/userfiles/files/miletil.pdfIn PDF document text
    • https://www.inkfactory.pk/wp-content/plugins/formcraft/file-upload/server/content/files/16077c7bded9f7---51833513120.pdfIn PDF document text
    • https://alllegaltask.com/wp-content/plugins/super-forms/uploads/php/files/cqdj8j6cvho0iu9jpsltq5khht/lezodesalolu.pdfIn PDF document text
    • https://alllegaltask.com/wp-content/plugins/super-forms/uploads/php/files/dkgv1kot97f737rll7djbrpg6v/rekurifegixagina.pdfIn PDF document text
    • http://salsainkonstanz.de/media/files/vonimimotekubom.pdfIn PDF document text
    • http://bascobrunswick.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160d2225a5a20c---63413690793.pdfIn PDF document text
    • http://www.realisthotel.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b9b02b51adb---69289107976.pdfIn PDF document text
    • https://halobysciton.com/wp-content/plugins/formcraft/file-upload/server/content/files/160906b59b6f32---nuzexonelukisa.pdfIn PDF document text
    • http://idcla.net/upload/files/nowogedesek.pdfIn PDF document text
    • http://xn----8sbpvg0afdbe.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/t6mom05n419nj1efv4ok9fh435/busowojojizazakumeba.pdfIn PDF document text
    • https://bwawarszawa.pl/upload/file/98382085481.pdfIn PDF document text
    • https://law.myvzl.com/wp-content/plugins/super-forms/uploads/php/files/2egne3pb7i73sobgjdl75tavbh/tapinabositixukezununor.pdfIn PDF document text
    • https://adreshosting.com/calisma2/files/uploads/92466324255.pdfIn PDF document text
    • http://kstarsmall.net/userfiles/file///87774021629.pdfIn PDF document text
    • http://circuitvietnamcambodge.com/hinhanh/file/38865512125.pdfIn PDF document text
    • https://bataretak.com/img/files/file/22982221588.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/fzgW7-mxBc0/uplcv?utm_term=exercice+conjugaison+anglais+tous+temps+pdfPDF 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_off0000da0b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA0B 11276 bytes
SHA-256: 88fb265b6cea46c478e3e03621756471f028badd498be89f41afb43b7500f353
font_01_sfnt_off0000f448.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF448 20108 bytes
SHA-256: 9c41c1f0069309e550b0fe70fc6600e752707e396a6606cc3f8b7f7257719304
font_02_sfnt_off0001271a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1271A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1