Malicious PDF — malware analysis report

Static analysis result for SHA-256 273aaf278dd2601b…

MALICIOUS

PDF

83.4 KB Created: 2021-09-07 10:29:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: c78e3cf5531f33dc940eb10c9e4e88ff SHA-1: 4881b7b2395e8c072c9345efebd7d40fda518aa1 SHA-256: 273aaf278dd2601b2e08c766782be0c90e130dd0f57cbacda811d8c8fea7cb33
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF contains embedded JavaScript and numerous external URIs, many of which point to compromised WordPress sites or disposable hosting, forming a link farm. The embedded JavaScript likely facilitates the redirection or further malicious activity. The ClamAV detection and ML classifier strongly indicate malicious intent, consistent with phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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://fine-cottage.ru/userfiles/file/zilijolujazumewodevu.pdf In PDF document text
    • https://12shio2.com/contents//files/jaguzasumegil.pdfIn PDF document text
    • http://doreenindiatours.com/userfiles/file/45990692415.pdfIn PDF document text
    • http://mail-business.ru/uploads/file/33248186989.pdfIn PDF document text
    • https://criteriacambio.com.br/wp-content/plugins/super-forms/uploads/php/files/msj2jh402rdqvube3ejhbif331/pufixasorikepenuzedevoro.pdfIn PDF document text
    • https://www.projectorrentals.com/wp-content/plugins/formcraft/file-upload/server/content/files/16076792f2dbb2---mefuxebuzas.pdfIn PDF document text
    • http://qboardapp.com/wp-content/plugins/super-forms/uploads/php/files/fbd13d1bd50a97f6266e97ebfd9af540/savewoponipat.pdfIn PDF document text
    • http://skyrun-arser.com/js/fckeditor/editor/filemanager/connectors/php/connector.php/upfiles/file/210630082432663764x92008.pdfIn PDF document text
    • http://vasilii-orlov.fun/wp-content/plugins/super-forms/uploads/php/files/f405d6f41b5c9b1e64cab3ccd48cc97b/88692610957.pdfIn PDF document text
    • http://musorcentrum.hu/files/article/file/tejurudepenemub.pdfIn PDF document text
    • https://portsidestrategies.com/wp-content/plugins/super-forms/uploads/php/files/b18af9a07d630b31fb976e6d1fac32a2/38227604304.pdfIn PDF document text
    • http://chagatea.ru/wp-content/plugins/super-forms/uploads/php/files/a31cd1631659f62cabe2dbedab7dcb3f/pesidumox.pdfIn PDF document text
    • http://nebovsem.ru/app/webroot/files/files/32925444898.pdfIn PDF document text
    • https://best-label.com/upload/files/60639749092.pdfIn PDF document text
    • http://www.airportlimofortlauderdale.net/wp-content/plugins/formcraft/file-upload/server/content/files/160a8464c58d64---sulisoluxivawegesabo.pdfIn PDF document text
    • http://www.afamaresme.org/wp-content/plugins/formcraft/file-upload/server/content/files/160be572947af6---tasiduwovosekorukujapapuv.pdfIn PDF document text
    • http://csim.jp/ckeditor/uploads/files/mitexudosa.pdfIn PDF document text
    • http://hk-keber.de/images/file/nunasuxugejabo.pdfIn PDF document text
    • http://fullcolorspandoeken.nl/userfiles/file/55254767767.pdfIn PDF document text
    • https://szabobuszrendeles.hu/files/files/75179147131.pdfIn PDF document text
    • https://vieclamday.com/userfiles/file/zibotexiwasuxabugasikev.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3vuEKuznOb8/uplcv?utm_term=pinkham+pediatric+dentistry+5th+edition+pdf+downloadPDF 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_off0000dbde.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDBDE 18516 bytes
SHA-256: b1bcc482622a3fd18286abce3b11057bd83b60d8614fed94722ac03447cccee4
font_01_sfnt_off00010c88.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10C88 11312 bytes
SHA-256: 149aaff5908486296c39cefe4a54c46edb4c44acaa2019813c27131480f27cc6
font_02_sfnt_off00012704.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12704 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1