Malicious PDF — malware analysis report

Static analysis result for SHA-256 6436a5eba4e7e088…

MALICIOUS

PDF

84.9 KB Created: 2021-09-13 17:59:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-25
MD5: 33099bf2223e1d2bde3b18bd0d1ffdbe SHA-1: a1d2f670e256b9d9eb2448e34d8a19c17d4a09b9 SHA-256: 6436a5eba4e7e0880d03ed0d6a4596288543ef3a0fdf6e01307204e8d0ebdb90
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 0.9964

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://piemonteforyou.it/userfiles/file/76200577128.pdf In PDF document text
    • https://webmodeli.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613c4b241965f---8643968202.pdfIn PDF document text
    • http://goodlack.cz/userfiles/file/96267706574.pdfIn PDF document text
    • https://cvsc.co/userfiles/file/74394442909.pdfIn PDF document text
    • https://www.sacproblemleri.com/wp-content/plugins/formcraft/file-upload/server/content/files/161394c814a465---22228164846.pdfIn PDF document text
    • http://chiengthai.com/file_media/file_image/file/69624267700.pdfIn PDF document text
    • https://chinese-wall.tw/upload/files/37811407147.pdfIn PDF document text
    • https://martan.es/cenavarra_userfiles/files/58558084692.pdfIn PDF document text
    • http://molenat-energies.fr/molenat.com/images/editor/file/20439012806.pdfIn PDF document text
    • http://www.nationaalgolfcongres.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16137ada1ea7be---zinef.pdfIn PDF document text
    • https://bocion.com/ckfinder/userfiles/files/zujowixidogedikiwej.pdfIn PDF document text
    • https://inprovituruguay.com/ckfinder/userfiles/files/togexixiniwava.pdfIn PDF document text
    • http://woonhuislift.info/wp-content/plugins/formcraft/file-upload/server/content/files/1613f576953676---kufomerasopimejej.pdfIn PDF document text
    • https://korankertas.com/contents/files/20822599289.pdfIn PDF document text
    • http://humidorio.de/ckfinder/userfiles/files/zorujetelorifixefedej.pdfIn PDF document text
    • http://www.taxivanclass.com/uploads/ckfinder/files/mivezodetelusule.pdfIn PDF document text
    • http://byecook.com/ckupload/files/wufitopupemawibimiru.pdfIn PDF document text
    • http://bikaji.zohukum.com/ckfinder/userfiles/files/mipuzuposejokabudufin.pdfIn PDF document text
    • http://meble-tk.pl/userfiles/file/79025440637.pdfIn PDF document text
    • https://3rproject.eu/ckfinder/userfiles/files/48149932629.pdfIn PDF document text
    • https://venusnvs.com/userfiles/file/dodebafilomu.pdfIn PDF document text
    • https://www.hospedeagora.com.br/wp-content/plugins/super-forms/uploads/php/files/gbvs9dldnso4eiorkta8c0robi/15509207270.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3CAf4wW3hvY/uplcv?utm_term=nassim+nicholas+taleb+antifragile+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_off0000e46e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE46E 18948 bytes
SHA-256: ec678e1a4e4fed77c7d46fa2aab01625617d35d04eb5915a9c32ebf926b87469
font_01_sfnt_off000114bc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x114BC 11184 bytes
SHA-256: 50057ee47deff2d512cc3e8843cbbc51d8be445a8dd52bf22aca5fcc12c4991a
font_02_sfnt_off00012e42.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12E42 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1