Malicious PDF — malware analysis report

Static analysis result for SHA-256 ef48dd9fcc517598…

MALICIOUS

PDF

73.4 KB Created: 2021-09-16 16:45:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 9b770fb7e004a56a70f1200223cb4ec3 SHA-1: 065bcce019500b502d284eae838f0bdb2f7c9e33 SHA-256: ef48dd9fcc5175987cf85ebbe85af12282acb8c9def3de510de7e0d330353f2c
156 Risk Score

Malware Insights

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

The sample was flagged by ClamAV as Pdf.Phishing.Trojan and an ML classifier indicated a high probability of maliciousness. Heuristics indicate the PDF contains a link farm pointing to compromised CMS upload storage and disposable hosting, suggesting a phishing or malware distribution lure. The embedded URLs likely lead to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://ketchas.ru/uplcv?utm_term=video+selber+machen+app+android PDF link annotation
    • https://xn--hjrnskadeakademien-mtb.se/userfiles/file/vopuwositejitiwugig.pdfIn PDF document text
    • http://autothudo.vn/upload/fck/file/pekefaz.pdfIn PDF document text
    • http://sous-mama.org/userfiles/file/kitoxuxidofosexa.pdfIn PDF document text
    • https://www.northamericatalk.com/wp-content/plugins/formcraft/file-upload/server/content/files/161316e74cb0c5---kopitazigurodexagesudo.pdfIn PDF document text
    • https://highlander-inn.com/assets/userfiles/files/44866963215.pdfIn PDF document text
    • http://putzlappenborner.at/editor_up/gizajuzavepasi.pdfIn PDF document text
    • https://samsungklima.net/upload/ckfinder/files/farufonesiv.pdfIn PDF document text
    • https://shevian.com/images/file/76255045075.pdfIn PDF document text
    • https://doellefjelde-mussemarked.dk/images/newsmail/file/70141351798.pdfIn PDF document text
    • http://metzpaintings.com/wp-content/plugins/formcraft/file-upload/server/content/files/161402d4d5ad91---82292567033.pdfIn PDF document text
    • https://callmarkinvestments.fortunekenya.com/callmark/files/89299268704.pdfIn PDF document text
    • http://drsuthichai.com/userfiles/files/45087017818.pdfIn PDF document text
    • http://agama-rc.com/upload/files/57293189432.pdfIn PDF document text
    • http://casavacanzesanvito.eu/userfiles/files/penivutigolewokoki.pdfIn PDF document text
    • https://veglifekc.org/wp-content/plugins/super-forms/uploads/php/files/66342101843.pdfIn PDF document text
    • https://institutdesante.org/userfiles/file/zegutadege.pdfIn PDF document text
    • http://sanitaerprofi.ch/fckeditor/editor/images/file/61226499969.pdfIn PDF document text
    • https://ourguarantees.com/userfiles/file/15800428806.pdfIn PDF document text
    • http://xn--or3bo5mvlb.com/data/editor/file/bapubemimalimon.pdfIn PDF document text
    • https://protrialse.eu/files/files/wurovovozakifobezi.pdfIn PDF document text
    • http://actionelectric.pt/www/wp-content/plugins/formcraft/file-upload/server/content/files/16134740f3f4f3---10537868331.pdfIn PDF document text
    • https://qeyeoptical.com/ckeditor/ckfinder/userfiles/files/wogurujufe.pdfIn PDF document text
    • http://dezis.ru/uploads/files/panan.pdfIn PDF document text
    • http://www.grupoaccs.net/ckfinder/userfiles/files/dubes.pdfIn PDF document text
    • 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_off0000b94b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB94B 17744 bytes
SHA-256: 14895d7535ecda0807a653c3c686a7b5d42b75ef9e6fa55deee2355e87634544
font_01_sfnt_off0000e647.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE647 10788 bytes
SHA-256: 17e9112d248e89550c0271411a7c6299339d76d1514bde3e6cc91727a8a9d0cb
font_02_sfnt_off0000fea1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFEA1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1