Malicious PDF — malware analysis report

Static analysis result for SHA-256 78d4bcd572c8bcb4…

MALICIOUS

PDF

76.3 KB Created: 2021-10-07 02:08:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 20b1dfccc8a88d339fc2b4af2cb8fa50 SHA-1: 51f7bed718d6a87d9071f395fc14be246d648c21 SHA-256: 78d4bcd572c8bcb4bcdc32645effc0de697cfded65f8557f924ae857ca37f719
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm on disposable domains, with numerous distinct hosts and links. The embedded URLs point to various unknown PDF files, suggesting a redirection or download mechanism.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9908

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://hamzakocakoglu.com/userfiles/file/91347819381.pdf In PDF document text
    • http://gzky.cn/dubeite/ckfinder/userfiles/files/20210920_035247.pdfIn PDF document text
    • https://aluminiosarla.com/userfiles_arla/files/jogutu.pdfIn PDF document text
    • http://www.fdconsult.qa/public/uploads/cms_files/8362266788.pdfIn PDF document text
    • http://www.ekoforte.com/upload/file/76617801389.pdfIn PDF document text
    • http://nessium.net/userfiles/file/xegifuxivavi.pdfIn PDF document text
    • http://www.tempshift.com/app/webroot/files/uploadimagesfile/fazixuzob.pdfIn PDF document text
    • http://deborahmayerlawoffices.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/sizezaniwevafaraposowo.pdfIn PDF document text
    • https://training-access.com/upload/file/65982643209.pdfIn PDF document text
    • http://www.cemeba.com/uploads/ckfinder/files/58582591576.pdfIn PDF document text
    • http://plncse.hu/php_data/file/kijidilu.pdfIn PDF document text
    • http://telecycling.org/files/file/liximuvilun.pdfIn PDF document text
    • https://mailing.crpm.ch/ck/ckfinder/userfiles/files/lonom.pdfIn PDF document text
    • http://elhammagazine.com/ckfinder/userfiles/files/2589259707.pdfIn PDF document text
    • http://ilovehikari.com/uploads/files/sivasomiwope.pdfIn PDF document text
    • http://gbfrjournal.org/pds/userfiles/files/46353145319.pdfIn PDF document text
    • http://mmsmarin.com/imgimage/file/fokez.pdfIn PDF document text
    • http://hoinhikhoavn.com/img/files/wixerojotutol.pdfIn PDF document text
    • https://planet-pvc.com/upload/files/pifokagafis.pdfIn PDF document text
    • http://skontrolsengineering.com/file_media/file_image/file/88260375282.pdfIn PDF document text
    • http://jonme.net/ckupload/files/78125886332.pdfIn PDF document text
    • http://ipjanah.ir/wp-content/plugins/super-forms/uploads/php/files/uueugg5n7tks5lqml9v8oesuqr/mediworanabiwisaziri.pdfIn PDF document text
    • http://xn----ftbkdcamitb5h.xn--p1acf/files/fck/file/93041996826.pdfIn PDF document text
    • http://farmaciacogliate.it/userfiles/files/77455182265.pdfIn PDF document text
    • http://savaksangida.com/resimler/files/taxudeluxazati.pdfIn PDF document text
    • https://smobiil.eu/userfiles/files/waxositefotupalovugemagak.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3CAf4wW3hvY/uplcv?utm_term=the+modern+french+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_off0000c4e7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC4E7 18652 bytes
SHA-256: d208ca36b8d381f79c997d5d49116410c27057e00e49f75220af7beee0c242c6
font_01_sfnt_off0000f46d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF46D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010c84.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10C84 10280 bytes
SHA-256: d7ab4db57aff1fa67e8904b32cea847316087e9e31f4c19df63324323df316cb