Malicious PDF — malware analysis report

Static analysis result for SHA-256 cb281c03b368fb22…

MALICIOUS

PDF

83.8 KB Created: 2021-10-09 01:12:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 4444e1681f3f828cb07c291169d06e47 SHA-1: f9aeaa1e6a05a0033a8404e5d3256e3e905fb08f SHA-256: cb281c03b368fb2269dc36c0881a4c2909c8ace8c76920b10e5fcfbcfee8b077
134 Risk Score

Malware Insights

MITRE ATT&CK
T1059.007 JavaScript T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript, a common technique for executing malicious code within documents. The heuristic PDF_SEO_DISPOSABLE_LINK_FARM and the numerous external URLs suggest a phishing or spam campaign aimed at driving traffic to potentially malicious sites. The ML classifier and ClamAV detection strongly indicate malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9911

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
  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://inwebjor.ru/uplcv?utm_term=how+to+answer+what+do+you+want+to+learn+from+this+internship PDF link annotation
    • https://nexapos.com/upload/files/89669896474.pdfIn PDF document text
    • http://megalaserasia.com/upload///tibova.pdfIn PDF document text
    • https://ltssinternational.com/res/wysiwyg/file/79718721487.pdfIn PDF document text
    • http://csc021.com/userfiles/file/20211001145124_rwhlxf.pdfIn PDF document text
    • https://martan.es/cenavarra_userfiles/files/basolulo.pdfIn PDF document text
    • https://samngaimarble.com/html_upload/file/59944331484.pdfIn PDF document text
    • http://brighterhealthcare.co.uk/wp-content/plugins/super-forms/uploads/php/files/6ihue35g7dmfau29ekvm0ke9f4/koriwigikejifazezixebepu.pdfIn PDF document text
    • https://desmar.cl/gestion/admin/images/upload/file/71511197389.pdfIn PDF document text
    • http://www.lbtfilm.com/uploads/files/43364770388.pdfIn PDF document text
    • http://federicozucchettiarchitetto.eu/userfiles/files/dutoteralewapajor.pdfIn PDF document text
    • http://www.dialog-seversk.ru/jsplugins/ckfinder/userfiles/files/fivenofonajelul.pdfIn PDF document text
    • https://beautifullifeuk.com/wp-content/plugins/super-forms/uploads/php/files/2a5ac7fc6275b901009ee7b7c1b12cd3/25289259514.pdfIn PDF document text
    • http://autosklo.sk/pictures/file/rakaxumedikidipizojenobof.pdfIn PDF document text
    • http://soc-in.com/data/media/files/83483210735.pdfIn PDF document text
    • http://vagyonvedelemszolnok.hu/admin/fck_upload/file/tanenawoj.pdfIn PDF document text
    • https://eletmodguru.hu/files/files/95730709367.pdfIn PDF document text
    • https://www.bnbtravels.com/ckfinder/userfiles/files/xalasetabivupojupukoriz.pdfIn PDF document text
    • http://eg-connect.com/php_codes/Scott/VieauAssociates/code/userfiles/file/rowiguvitofigaxito.pdfIn PDF document text
    • https://livewireeventz.com/userfiles/file/ziluxu.pdfIn PDF document text
    • http://paintmaster.hu/js/ckfinder/userfiles/files/loresuraxora.pdfIn PDF document text
    • https://xetnghiemadndanang.com/upload/userfiles/files/fifonowalimu.pdfIn PDF document text
    • https://tktravelkorea.com/FileData/ckfinder/files/20210905_1CA358E1B34A0246.pdfIn PDF document text
    • https://www.bevillelecomte.com/ckfinder/userfiles/files/pijewiresejavulawagiwitij.pdfIn PDF document text
    • https://firsatoyun.com/calisma2/files/uploads/todidutavinosejiveni.pdfIn PDF document text
    • http://kidneytracker.com/ckfinder/userfiles/files/46968288411.pdfIn PDF document text
    • http://files.ibiza-ferien.de/file/wuvexoxuwumoz.pdfIn PDF document text
    • http://maristaslardero.es/userfiles/file/diwuzegilidobe.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_off0000ddab.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDDAB 11056 bytes
SHA-256: 0a2f08202db845f705534b4f4da1a6450e2aed07d43593ca6ff36a6c14bb1fee
font_01_sfnt_off0000f739.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF739 19176 bytes
SHA-256: ba92f09e7f070885977a7462cb58448ddd8a0273c6fcbf26fb5cf7c3e4b5ed45
font_02_sfnt_off000128e1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x128E1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1