Malicious PDF — malware analysis report

Static analysis result for SHA-256 5bf251fa1b308ed8…

MALICIOUS

PDF

80.5 KB Created: 2021-09-17 19:08:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: c2c7d89a4298986f46ed0a8f5b71bf6a SHA-1: 31aa0ddf618d2b4f28937e686a7d56eb94c4ae74 SHA-256: 5bf251fa1b308ed81f2deac276143d075d398a4e3e1c6af977e916ba4f74876a
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains a large number of embedded URLs, many of which point to compromised websites or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with techniques used to lure users to malicious sites.

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 https://www.cir.cloud/wp-content/plugins/formcraft/file-upload/server/content/files/1613f4435bb36c---kawebekafa.pdf In PDF document text
    • http://andersonlawdecorah.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/27591754218.pdfIn PDF document text
    • http://herborgthailand.com/file_media/file_image/file/16653925292.pdfIn PDF document text
    • http://mail-business.ru/uploads/file/paxasekekazuxofisutidupo.pdfIn PDF document text
    • https://noelex22.org/userfiles/file/56517236961.pdfIn PDF document text
    • https://cityface.cz/res/file/66296312069.pdfIn PDF document text
    • http://globalone-mould.com/gbw/fckfiles/20210908102436.pdfIn PDF document text
    • https://indiachristian.org/uploads/files/80178823875.pdfIn PDF document text
    • https://bestmiamiturf.com/wp-content/plugins/super-forms/uploads/php/files/af556a8dde7917a3532edd559f0357d6/40024651660.pdfIn PDF document text
    • http://ghinelliarchitettura.it/userfiles/files/15416874600.pdfIn PDF document text
    • http://dar-tom.pl/userfiles/file/nuvoworozugatovozebi.pdfIn PDF document text
    • http://serbanindustrialconstruct.ro/uploads/files/72794782789.pdfIn PDF document text
    • http://kechengchem.com/upload/files/64571519705.pdfIn PDF document text
    • https://aparcaderoshaddaichile.cl/uploads/images/files/77448080778.pdfIn PDF document text
    • https://rmissio.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1613bfc758f7e8---vexudexadexarifozapida.pdfIn PDF document text
    • http://kalmi.ru/upfiles/files/90227216267.pdfIn PDF document text
    • https://superpackeg.com/userfiles/file/zeromiviwupozaket.pdfIn PDF document text
    • http://www.nomorcantikjoss.com/file/digarodorisutudolin.pdfIn PDF document text
    • https://viettincapital.vn/upload/files/joromam.pdfIn PDF document text
    • http://se-ty.ru/uploads/userfiles/file/98881168066.pdfIn PDF document text
    • http://newdimension.su/userfiles/file/28118279713.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/GLLx1DTH0VQ/uplcv?utm_term=what+color+do+you+get+when+you+mix+orange+and+yellowPDF 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_off0000d3e1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD3E1 11044 bytes
SHA-256: 4abf8b796f595d4cd82751e078cc9e1620f3facbd888810de894cf67b919266d
font_01_sfnt_off0000ed3e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED3E 18060 bytes
SHA-256: 74ae6881efebc5c8725adc7ccda0965a5a478ec5e6aae52aeab94c9e108976ab
font_02_sfnt_off00011bc1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11BC1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1