Malicious PDF — malware analysis report

Static analysis result for SHA-256 a8042dc280ab823b…

MALICIOUS

PDF

79.2 KB Created: 2021-08-19 14:58:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 6b097e75f3a4f1692c089e6509e467c9 SHA-1: 2983723959d6f8a889a3ad8b72b1e65d0c3720ff SHA-256: a8042dc280ab823bbc3754b681624a3a837d253dad637fd807c4f9192997315a
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF document containing embedded JavaScript and a large number of external links, many of which point to compromised WordPress sites. This indicates an attempt to lure users to malicious websites, likely for phishing or further malware distribution. The ClamAV detection and ML classifier strongly support its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

Heuristics 7

  • 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.
  • 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://drafthe.ru/uplcv?utm_term=exercices+cm2+fractions+d%C3%A9cimales+imprimer PDF link annotation
    • http://labcoop-jsc.com/wp-content/plugins/super-forms/uploads/php/files/dg1kom02grkmb5c13824ai1lrs/naror.pdfIn PDF document text
    • http://aiswaryamatrimonials.com/fck_uploads/file/3585417011.pdfIn PDF document text
    • http://hotelamadeustorino.com/userfiles/files/firadajiwosekuzaxupevo.pdfIn PDF document text
    • http://dreamcatcherltd.com/userfiles/file/2882313073.pdfIn PDF document text
    • https://siam-royal-view.ru/data/files/tipenuvisepujeb.pdfIn PDF document text
    • https://cal.lighting/wp-content/plugins/super-forms/uploads/php/files/bb40f9a5ec4dce9df495a813d39e4a46/sirapiriwulafigowaxevopi.pdfIn PDF document text
    • http://artmetinc.com/wp-content/plugins/formcraft/file-upload/server/content/files/160af58c228c88---golojine.pdfIn PDF document text
    • http://lookkorea.net/userfiles/file/pujobuli.pdfIn PDF document text
    • https://crownprolaw.com/userfiles/Proj_Name//files/15925683628.pdfIn PDF document text
    • http://chono.mn/uploads/userfiles/files/dugiwamimawodumavuleroj.pdfIn PDF document text
    • https://www.histoiresdegroupes.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607873374d092---limalarerezumepirabasu.pdfIn PDF document text
    • https://youstore21.com/wp-content/plugins/super-forms/uploads/php/files/5ce7fbaf015bb3e1b72dd57d03c94782/jomovuvedikuzofebegokosab.pdfIn PDF document text
    • https://asiabiru.com/contents//files/wavivisodo.pdfIn PDF document text
    • https://aliencosmicexpo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607593c6aaef8---49571151743.pdfIn PDF document text
    • https://successalpha.team/upload/files/71680433750.pdfIn PDF document text
    • https://media-get.com/userfiles/files/sabanekiza.pdfIn PDF document text
    • https://www.vedaaz.com/wp-content/plugins/super-forms/uploads/php/files/9b3eed3eaab7407820fbd1a0cc0f6098/xixitogijorafowatamaz.pdfIn PDF document text
    • https://worldcastlive.com/userfiles/file/sedoxefaruxi.pdfIn PDF document text
    • http://protech.com.ng/wp-content/plugins/formcraft/file-upload/server/content/files/160aa514554147---jawiwemasunosi.pdfIn PDF document text
    • https://tfnd.org/wp-content/plugins/super-forms/uploads/php/files/be83f86f6ee95ab54a34e8d9a89f82b9/49448711214.pdfIn PDF document text
    • http://www.jacenter.org/js/ckfinder/userfiles/files/58595553407.pdfIn PDF document text
    • http://bualuang101.com/backoffice/upload/files/katin.pdfIn PDF document text
    • https://too.kg/wp-content/plugins/super-forms/uploads/php/files/df752f6ddc36119cd5997307e0ee1678/nopesatewisekibizuxoreju.pdfIn PDF document text
    • http://doverhighschoolhalloffame.com/clients/2/2d/2d76883e1086210ef8e2c43836b0327f/File/zozogaselabexebutajisofu.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_off0000ce50.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCE50 17068 bytes
SHA-256: 79e7c7cd95b87176bfc99fd162b8a72c92f38f74391bfb4c37edddce7e2d7009
font_01_sfnt_off0000f95a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF95A 11140 bytes
SHA-256: 852b5627a3a064b700d743b7e012fc283cfda9459be6ffe32f70be6fd9a0b62c
font_02_sfnt_off00011325.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11325 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1