Malicious PDF — malware analysis report

Static analysis result for SHA-256 cda9da042c687a61…

MALICIOUS

PDF

69.7 KB Created: 2021-09-29 00:37:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: d8a2ba1a0ceedcd752b8c64e64c3b9e0 SHA-1: 90cf4ea8872e89875eb840d090076afce4c76982 SHA-256: cda9da042c687a618f6f553f344f7e3ef0705eaa06c590e84cb52e7ddf63a06d
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The sample was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The PDF contains numerous embedded URLs, with one heuristic identifying it as a link farm on disposable hosting. While no scripts were extracted, the presence of external URIs and the link farm characteristic suggest the PDF is intended to redirect users to malicious sites, likely for phishing or further payload delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9916

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 http://barudan.hk/UploadFile/file/20210929052109933.pdf In PDF document text
    • http://broadgatecapital.com/userfiles/file/59717574729.pdfIn PDF document text
    • http://angelofthewinds.org/ckfinder/userfiles/files/makanewamokovirazujuka.pdfIn PDF document text
    • http://china-guolin.com/filespath/files/20210902171306.pdfIn PDF document text
    • http://ruihuitax.com/files/file/xevanisi.pdfIn PDF document text
    • https://loyalangkorapartment.com/userfiles/file/15500923209.pdfIn PDF document text
    • http://maimungkorn.com/UserFiles/file/rukelajagafukovase.pdfIn PDF document text
    • http://terezszilvia.com/images/uploaded/file/65646746274.pdfIn PDF document text
    • http://www.jysunshine-hotel.com/up_files/file/kagomodezoletunezavolek.pdfIn PDF document text
    • http://xn--rssx31a7tec6p.com/upload/userfiles/files/20210912075855.pdfIn PDF document text
    • https://listapp.in/ci/userfiles/files/fimizoz.pdfIn PDF document text
    • http://smartvoicecom.com/userfiles/zofawunapulemax.pdfIn PDF document text
    • http://pogotowienaukowe.com/Upload/file/mogugisasasamuxudox.pdfIn PDF document text
    • http://issaproject.com/app/views/panel/ckfinder/userfiles/files/7616437186.pdfIn PDF document text
    • http://santeh.md/img/files/sarolabevotibavuz.pdfIn PDF document text
    • https://vidaleve.net/ckfinder/userfiles/files/83864233810.pdfIn PDF document text
    • https://marcvandewiele.com/userfiles/file/satumabomutikijodariwum.pdfIn PDF document text
    • http://xn--90ad5ackt1d.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/feeed9f36d8cfff5ad7220d2423793fe/99042912388.pdfIn PDF document text
    • http://finproekt-msk.ru/userfiles/file/lujazowubipurufimup.pdfIn PDF document text
    • http://gocoachfox.com/userfiles/file/xuxeror.pdfIn PDF document text
    • http://guowangcable.com/d/files/399790346.pdfIn PDF document text
    • http://yh-nutri.com/filespath/files/20210922001714.pdfIn PDF document text
    • http://connectcontrol.net/files/userfiles/files/vigifunutuw.pdfIn PDF document text
    • http://yuanjen.com/ckfinder/userfiles/files/76112692336.pdfIn PDF document text
    • https://finestblogger.de/wp-content/plugins/super-forms/uploads/php/files/hg2h88s5jm5o7kj8fpqmjg7srq/kakerera.pdfIn PDF document text
    • https://linhan.xelinhan.vn/userfiles/file/54136555832.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/DOqCt-cVA4I/uplcv?utm_term=amazon+prime+video+android+ukPDF 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_off0000b331.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB331 10540 bytes
SHA-256: 89f0b9663579f291f164786700bc105ef9bcccf80d530b65e20edfb7feffde9e
font_01_sfnt_off0000cb34.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCB34 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e346.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE346 15060 bytes
SHA-256: 0fd17349462bfa1302f1f3f2e4e21aaf141bad0f62e847d6a33dfdfe664263f9