Malicious PDF — malware analysis report

Static analysis result for SHA-256 cd19898d4ab58dc3…

MALICIOUS

PDF

84.9 KB Created: 2021-09-21 09:10:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 0c9ddb384e51ac6d9f3595898c776ffb SHA-1: 5b7067d403faa770fa9a8e43837c108de9388f3c SHA-256: cd19898d4ab58dc37b51f67b6373c25a272d982a710ecae1ac698f2dee8ab9c1
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The ML classifier and ClamAV detection strongly indicate malicious intent. The PDF contains numerous links to external websites, many of which appear to be hosted on compromised or disposable domains, suggesting a phishing or malware distribution scheme. The presence of PDF_SEO_DISPOSABLE_LINK_FARM and PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM heuristics further supports this, indicating the document is part of a link farm designed to obscure the true destination.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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=mk+gandhi+autobiography+pdf PDF link annotation
    • http://mpti.ru/userfiles/file/53170787954.pdfIn PDF document text
    • https://yenicekentkaplicasi.com/userfiles/file/32473439739.pdfIn PDF document text
    • http://thebrownbag.vn/upload/files/natubaxepezipagekuxomov.pdfIn PDF document text
    • http://01host.ru/userfiles/files/ranebojugajapesizuseg.pdfIn PDF document text
    • https://stotex.rs/files/jujaz.pdfIn PDF document text
    • http://jjw-led.com/userfiles/file/94328085757.pdfIn PDF document text
    • http://az4group.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/161387515c244d---13559827626.pdfIn PDF document text
    • http://jockmurray.com/wp-content/plugins/formcraft/file-upload/server/content/files/161341a703e236---13641664955.pdfIn PDF document text
    • https://hbfilm.ca/resimler/files/57168795311.pdfIn PDF document text
    • http://workontext.ru/media/file/71062412657.pdfIn PDF document text
    • http://shlawllc.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/27680732545.pdfIn PDF document text
    • http://olympusflights.com/files/files/vejusasedunag.pdfIn PDF document text
    • http://congtyvima.com/images/Download/xefek.pdfIn PDF document text
    • http://gonvvama.net/filespath/files/20210907173438.pdfIn PDF document text
    • https://chuyennhakienvangvn.net/upload/files/50731094954.pdfIn PDF document text
    • https://ever-progress.com/upload/files/wewelonebijuvodesem.pdfIn PDF document text
    • http://candientuvibra.com/images/file/mudakezakatimisow.pdfIn PDF document text
    • http://lukoilmarine.com/ckfinder/userfiles/files/77506041957.pdfIn PDF document text
    • https://shturnev.com/files/foFKED/file/pegapumularetozareri.pdfIn PDF document text
    • http://www.rebranded.tv/wp-content/plugins/formcraft/file-upload/server/content/files/1613cf17dc5a60---70802458030.pdfIn PDF document text
    • https://jmtours.co/aym_image/files/demumagol.pdfIn PDF document text
    • https://hediyelikhanem.com/calisma2/files/uploads/47791525616.pdfIn PDF document text
    • https://ardiinerkh.mn/uploads/userfiles/files/mifabekiginiwetadekega.pdfIn PDF document text
    • http://gourmethousemacau.com/UploadFilesfile///57498846250.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_off0000e6fa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE6FA 17844 bytes
SHA-256: 6aab751113ce5e5945772a88677b52b2c2873193e91a132a5c76f9dc000cb649
font_01_sfnt_off00011561.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11561 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012d78.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12D78 10872 bytes
SHA-256: 938911a1a4d93b996e658f045a0c2fbff30549d539f4e4b396cba123afdd18e6