Malicious PDF — malware analysis report

Static analysis result for SHA-256 9db136fdcf26e9d8…

MALICIOUS

PDF

86.3 KB Created: 2021-09-08 19:41:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 4121e7d0502f9aba039b3cdcf3665ab7 SHA-1: 7c581ec9ad8d01ea8039280c5266ddfb833873bb SHA-256: 9db136fdcf26e9d82fb0febd020f8cfe23adf373c7c37be095a6b7226f0b6d06
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external URLs, many of which are hosted on disposable domains and appear to be part of a link farm, suggesting a phishing or malware distribution attempt. The ML classifier and ClamAV detection strongly indicate malicious intent. While no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with a spearphishing attachment designed to lure users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://drafthe.ru/uplcv?utm_term=system+design+document+sample+pdf PDF link annotation
    • http://www.consorcio.edu.pe/wp-content/plugins/formcraft/file-upload/server/content/files/161342ee24c64a---33841090759.pdfIn PDF document text
    • http://stphilomenaonline.org/userfiles/file/7043266715.pdfIn PDF document text
    • https://kalashad.com/userfiles/file/xikikurobi.pdfIn PDF document text
    • http://casms.org/atts/news-files/file/savowaxefetigusalorijizit.pdfIn PDF document text
    • http://tienhasteel.com/app/webroot/upload/files/tirojebanizisapozuwutatu.pdfIn PDF document text
    • http://skogsformedling.se/bilder_umeny/File/10887040311.pdfIn PDF document text
    • http://king-ber.com/UploadFiles/file/20210907100915216.pdfIn PDF document text
    • http://nktrading.qa/file/files/sowedorobavanutevawufebe.pdfIn PDF document text
    • http://kemenyseprosiklos.hu/upload/file/nadawifamimezu.pdfIn PDF document text
    • http://zabbeleecooking.com/ckfinder/userfiles/files/dofemotofumi.pdfIn PDF document text
    • http://vcelari.naceradec.cz/includes/ckfinder/userfiles/files/rutakomumalafado.pdfIn PDF document text
    • http://beijingxinzhi.com/userfiles/file/20210906184915_1830385616.pdfIn PDF document text
    • http://ceraunavoltapizzeria.it/userfiles/files/rixibexezotutomekam.pdfIn PDF document text
    • http://onishi-kyosendo.jp/archive/56089220135.pdfIn PDF document text
    • http://gruppocaminiti.it/userfiles/files/kusumomewemozawetomalunid.pdfIn PDF document text
    • https://history.tlshaa.org.tw/ckfinder/userfiles/files/vafotobitopusojute.pdfIn PDF document text
    • http://jlicentral.com/images/authors/file/10536834853.pdfIn PDF document text
    • http://worldsocialistpartyindia.org/ckfinder/userfiles/files/vekesametetezopadibojix.pdfIn PDF document text
    • http://miyozenemeryville.com/uploads/files/24585815830.pdfIn PDF document text
    • https://kingwaterpure.com/ckfinder/userfiles/files/85673297914.pdfIn PDF document text
    • http://sushinamu.com/uploads/files/kajekaxezule.pdfIn PDF document text
    • https://butagallery.com/userfiles/files/69205200773.pdfIn PDF document text
    • http://mikailang.com/userfiles/file/20210907130217_1267736295.pdfIn PDF document text
    • http://hangtatmj.com/userfiles/domanijin.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_off0000eb17.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB17 17804 bytes
SHA-256: f711e052eb4690dcdc18c838e76840783f384be0f90d9cef3acebe4d1ef318ee
font_01_sfnt_off00011912.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11912 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00013129.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13129 11152 bytes
SHA-256: eeb474ea4fc69afa0976bbb6e98e27e53e5c7bcd18af954850a94ec3c9ee6795