Malicious PDF — malware analysis report

Static analysis result for SHA-256 85c1b4b4d58d02ce…

MALICIOUS

PDF

81.0 KB Created: 2021-09-18 11:09:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 57c03aded9d605ecfe20fabd80e864d3 SHA-1: e7e96d2b378732b03420709f40fc0cb325415b2d SHA-256: 85c1b4b4d58d02ceb970964f061412ac6eb525c1ff3b44f88f2f0e16b8adcfbc
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The presence of embedded JavaScript and a link farm pointing to potentially compromised WordPress upload storage indicates malicious intent. The embedded JavaScript likely serves to execute malicious code or redirect the user to a phishing site. The link farm structure, combined with the ClamAV detection and ML classifier flagging, strongly suggests this PDF is designed for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9949

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 https://forumsevens.com/images/file/mimujedolobe.pdf In PDF document text
    • https://duragloss.pl/userfiles/file/fejumonifojun.pdfIn PDF document text
    • https://masterok-kovka.ru/wp-content/plugins/super-forms/uploads/php/files/9351fa9c545d5c162ba0a2bd44c29c96/53013130229.pdfIn PDF document text
    • https://cbconsulting112.ca/userfiles/files/91653481106.pdfIn PDF document text
    • http://sweed-trans.eu/ckfinder/userfiles/files/78246558711.pdfIn PDF document text
    • https://karapinler.com/calisma2/files/uploads/45599216042.pdfIn PDF document text
    • http://ohmamakitchen.com/uploads/files/69957740341.pdfIn PDF document text
    • http://reckdance.pl/userfiles/file/gozibupezi.pdfIn PDF document text
    • https://xistenze.nagydavid.com/files/files/juzujovik.pdfIn PDF document text
    • https://www.budgetskemaet.dk/wp-content/plugins/formcraft/file-upload/server/content/files/16130ebc62b2f2---vulotunizug.pdfIn PDF document text
    • https://www.sblending.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16136f3b3282bc---58296598570.pdfIn PDF document text
    • http://gammatradings.com/userfiles/file/63946940048.pdfIn PDF document text
    • http://nhagiatxanh.com/public/default/ckeditor/files/kaseximek.pdfIn PDF document text
    • https://lhorizon.ca/uploadHorizon/file/18790723259.pdfIn PDF document text
    • https://www.koreayokogawa.com/ckfinder/userfiles/files/sirusinutov.pdfIn PDF document text
    • http://midoriku.zaitakunet.jp/app/webroot/upload_images/files/mirelanizu.pdfIn PDF document text
    • http://m-styleauto.com/js/upload/files/99642440047.pdfIn PDF document text
    • https://rgcsmt.org/ckfinder/userfiles/files/82473637744.pdfIn PDF document text
    • http://badgerhillfarm.uk/10246685764.pdfIn PDF document text
    • http://elite-nails.pl/Upload/file/moxokugejuvaxutajisibosir.pdfIn PDF document text
    • http://hotelbellevuepalermo.com/userfiles/files/gabaruzenusoxo.pdfIn PDF document text
    • http://orosweb.hu/ckfinder/userfiles/files/letini.pdfIn PDF document text
    • http://sarljarry.com/userfiles/file/45426182128.pdfIn PDF document text
    • http://imdmotors.com/uploadfile/file/2021090407155945.pdfIn PDF document text
    • http://issaproject.com/app/views/panel/ckfinder/userfiles/files/rinugotojoriwiwim.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/S30rS-6n6vg/uplcv?utm_term=pokemon+x+2ds+romPDF 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_off0000d9f3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD9F3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f20a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF20A 10324 bytes
SHA-256: 8a3b0292beca37859c8a3c49ed37d7a9d995e542a3c58abb0dcc760734eb4a75
font_02_sfnt_off0001095c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1095C 17364 bytes
SHA-256: 3a75253d9e4b2bfd7252b934a1ea6862686eab4ea935f87ec19e716f5fe82ef9