Malicious PDF — malware analysis report

Static analysis result for SHA-256 bc7fa3dea1eed903…

MALICIOUS

PDF

71.1 KB Created: 2021-10-02 15:32:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 9325478b099bf99fce399c47ef5c0d94 SHA-1: 097e426ffd98876b0295bd9318c3e6b4d6a69612 SHA-256: bc7fa3dea1eed9035d67ad1ef1aedb7373749152c2fc90763533b23a2041a7e8
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links to external websites, many of which are hosted on disposable domains or compromised CMS uploads, indicating a link farm designed to redirect users to malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent. While no scripts were explicitly extracted, the PDF structure and heuristic firings point towards a phishing or malware distribution scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9916

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://jiehuist.com/userfiles/files/71395965497.pdf In PDF document text
    • http://waterlootour.com/FileData/ckfinder/files/20210916_CDC9DC4D82E91643.pdfIn PDF document text
    • http://dienlanhhuubinh.com/upload/files/56712508308.pdfIn PDF document text
    • http://phutungvespaco.com/luutru/files/64458318920.pdfIn PDF document text
    • https://papiratisk.cz/soubory/kudinopulaxe.pdfIn PDF document text
    • https://goldfieldssanddrags.com.au/ckfinder/userfiles/files/makominezafabeginoze.pdfIn PDF document text
    • http://tinhdauvietnam.vn/upload/files/10919211259.pdfIn PDF document text
    • http://hitecds.com/userfiles/file/dekikesosimalo.pdfIn PDF document text
    • http://noxsun.com/jingkelun/userfiles/files/20210915123430.pdfIn PDF document text
    • http://bbfrontedelmare.com/userfiles/files/dipeputesokubibunum.pdfIn PDF document text
    • http://lookupagency.es/wp-content/plugins/formcraft/file-upload/server/content/files/161364d5f7b2e8---40326969163.pdfIn PDF document text
    • http://3handseg.com/wp-content/plugins/formcraft/file-upload/server/content/files/161393279942ae---zugupekebu.pdfIn PDF document text
    • https://coffotea.com/uploads/files/202109160858449072.pdfIn PDF document text
    • https://eric-parnes.com/ckfinder/userfiles/files/7790181713.pdfIn PDF document text
    • https://mollis.rs/files/19016779744.pdfIn PDF document text
    • http://www.scmphotography.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/161463f622fa93---pekukafifazowafa.pdfIn PDF document text
    • http://drsuthichai.com/userfiles/files/18782461395.pdfIn PDF document text
    • http://vipnjl.com/userfiles/files/22565371601.pdfIn PDF document text
    • http://www.cuerpomenteyespiritu.es/wp-content/plugins/formcraft/file-upload/server/content/files/1612eb3b18db5f---97198514348.pdfIn PDF document text
    • https://deltaguvenlik.net/userfiles/file/silugitavejasexa.pdfIn PDF document text
    • https://brianhigbielaw.com/UserFiles/file/23176755141.pdfIn PDF document text
    • https://arte-salon.ru/upload_picture/wavisexadofogimezeper.pdfIn PDF document text
    • https://www.jdconstinc.com/ckfinder/userfiles/files/xarirenajorowirodukipuz.pdfIn PDF document text
    • https://braindevelopmentmaps.org/userfiles/files/xotaj.pdfIn PDF document text
    • https://thriveelearning.com/wp-content/plugins/super-forms/uploads/php/files/64e0967481651dcbfad4a9fb91f1809f/92483073235.pdfIn PDF document text
    • http://sanmorales.es/userfiles/files/ravezisedatemonuxalasolek.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/ngfLrbzwjls/uplcv?utm_term=ramadan+coloring+pages+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_off0000b593.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB593 10908 bytes
SHA-256: 1d7c7fb3bbc90091f37c038060867e71ca28602a63c1e0028731f791c019c29e
font_01_sfnt_off0000ce8c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCE8C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e69e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE69E 15800 bytes
SHA-256: a8a0a7d714e16c2cea34d195364ae1ccb617b9c87b1489036ea24538a2dc0ee7