Malicious PDF — malware analysis report

Static analysis result for SHA-256 b43a9f534d53fd5b…

MALICIOUS

PDF

71.0 KB Created: 2021-09-27 19:30:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: f064c31604f520cc22b47bc60ae478d7 SHA-1: 260dba690bb07094c12e3b780707bab40c1429e2 SHA-256: b43a9f534d53fd5bc742041691624305f6d02426aa3a7cd6915d393f12f31690
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF file detected as malicious by ClamAV and an ML classifier. It contains embedded JavaScript and numerous external URIs, many of which point to compromised or disposable hosting, suggesting a phishing or malware distribution attempt. The embedded JavaScript likely facilitates the redirection to these malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.
  • 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 http://slxiang.com/v15/Upload/file/2021917912294149.pdf In PDF document text
    • http://canadanur.com/resimler/files/11901092120.pdfIn PDF document text
    • https://clearpatth.com/userfiles/file/pegoba.pdfIn PDF document text
    • http://totalfinance.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16130bfd1b2032---98719453923.pdfIn PDF document text
    • http://vidol.eu/userfiles/file/95291138819.pdfIn PDF document text
    • https://barcelonamedicalcenter.com/files/galeria/files/957529620.pdfIn PDF document text
    • https://retta-bg.com/userfiles/jinidasafufujerajalebufof.pdfIn PDF document text
    • http://highspiritsmusic.com/ckfinder/userfiles/files/ragiruboxegop.pdfIn PDF document text
    • http://caphegiabao.com/upload/fck/file/vurijeporubapubiwagodig.pdfIn PDF document text
    • https://hps-gruppe.com/wp-content/plugins/super-forms/uploads/php/files/f7upn3grs35h710ql1123nruk4/pufirubesejiroguviduzu.pdfIn PDF document text
    • https://kampusogrenciyurdu.com/file/65777212538.pdfIn PDF document text
    • http://epicridesnepal.com/files/wilibofokixotiw.pdfIn PDF document text
    • https://ctapigroup3.com/contents/files/20705328695.pdfIn PDF document text
    • http://www.cpiequipos.com/assets/images/user_files/files/56458115172.pdfIn PDF document text
    • https://minhkygroup.com/luutru/files/fetewagarowoxuluteja.pdfIn PDF document text
    • http://xn-----6kcaheblih5ab0a6afqbzoqe.xn--p1ai/ckfinder/userfiles/files/tinevugewi.pdfIn PDF document text
    • https://csmgh.net/pevron/www/img/file/zupajezobizamejol.pdfIn PDF document text
    • https://ciiinnovationsummit.com/ci/userfiles/files/88821706357.pdfIn PDF document text
    • http://www.bordadoindustrial.com/ckfinder/userfiles/files/87960587650.pdfIn PDF document text
    • http://queuemanagementsystems.com/wp-content/plugins/formcraft/file-upload/server/content/files/161423626ced5d---88095910355.pdfIn PDF document text
    • http://pantanalmsnews.com.br/ckfinder/userfiles/files/fepanasekalube.pdfIn PDF document text
    • https://parisautotravel.com/wp-content/plugins/super-forms/uploads/php/files/mldm77smhi31871ih4p1s24ng4/95420829203.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/ngfLrbzwjls/uplcv?utm_term=what+did+washington+do+about+the+whiskey+rebellionPDF link annotation
    • http://www.cst.rnu.tn/js/ckfinder/userfiles/files/67345704415.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_off0000b3e9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB3E9 15964 bytes
SHA-256: 047e4955887e9f52f190d8ee7ebff25ea2cd750ef9edb385e44f9824bc2ef22f
font_01_sfnt_off0000dc39.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDC39 11052 bytes
SHA-256: 392fb744eeb299ecf03ef6fe1d531975671eac9e46d6d4305e7f71ac42cc3df7
font_02_sfnt_off0000f5c6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF5C6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1