Malicious PDF — malware analysis report

Static analysis result for SHA-256 bd1b157d52c13c1d…

MALICIOUS

PDF

85.5 KB Created: 2021-09-04 17:26:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 57173e916c3d021e88c11263963ea3bb SHA-1: 0279a4b15cdf40df64b5b35ce117ccb58614476b SHA-256: bd1b157d52c13c1de6f1f5d93d6819db83eddf416ab172c5e100c267a2c26c23
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous external URIs and links to compromised WordPress upload directories, indicating it functions as a link farm. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or distributing further malware. The document body is unreadable, but the heuristic findings point to a malicious link distribution scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 6

  • 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.
  • 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://crysiq.ru/uplcv?utm_term=toshiba+lcd+tv+32+inch+manual PDF link annotation
    • https://noble-worldwide.com/wp-content/plugins/super-forms/uploads/php/files/fdc041abad5aee08de5e8b86a020c73e/649115348.pdfIn PDF document text
    • http://www.evisiontiendaonline.com/ckfinder/userfiles/files/64480132209.pdfIn PDF document text
    • http://ar-intl.net/wp-content/plugins/super-forms/uploads/php/files/4f3cu62754gsdo3nmpgm9a44d5/lasidelepubugirulubasuvu.pdfIn PDF document text
    • https://markzone.az/wp-content/plugins/super-forms/uploads/php/files/ghumbjmbprfjg48crq25463uod/91237856861.pdfIn PDF document text
    • https://useoneconvo.com/wp-content/plugins/super-forms/uploads/php/files/7d41db697319bc413d300fc08059fe75/74403036502.pdfIn PDF document text
    • http://gryfarmerskie.pl/pliki_wyswig/files/58012376286.pdfIn PDF document text
    • http://madmojo.com/fckupload/file/wanikebemevipa.pdfIn PDF document text
    • https://amenagementsoleil.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d64acc7816---jonizikipudujagarufawibo.pdfIn PDF document text
    • https://mikludava.lt/images/files/6941181664.pdfIn PDF document text
    • https://northstarexecutivesearch.com/wp-content/plugins/super-forms/uploads/php/files/dbbe95ea7241fd8f40790ae63cdfad8c/vugabajigirum.pdfIn PDF document text
    • https://www.arc-welding.co.uk/wp-content/plugins/super-forms/uploads/php/files/885ivgrqth0bc5g6amc1bu8kht/niwazovafokitopaki.pdfIn PDF document text
    • http://puisan.ru/uploads/file/60251568568.pdfIn PDF document text
    • http://aaykpn.com/uploads/editor/files/5210206052.pdfIn PDF document text
    • http://haliburtonhighlandsheritage.ca/userfiles/file/kalejavidaj.pdfIn PDF document text
    • https://drrajanmahtani.com/userfiles/files/gosifutipof.pdfIn PDF document text
    • https://aspaeng.com/files/image/files/zilimusosikumigejujevabiw.pdfIn PDF document text
    • http://hangnhatbanonline.com/upload/files/9824442871.pdfIn PDF document text
    • http://expresskaliski.info/file/6281449676.pdfIn PDF document text
    • https://realimpacto.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1607b2d352dd58---28614912015.pdfIn PDF document text
    • http://hoangduy.vn/vn/files/53708426908.pdfIn PDF document text
    • http://anhuifan.com/upload_fck/file/2021-5-21/20210521170111988996.pdfIn PDF document text
    • http://aylabawadi.ae/userfiles/file/rejijujaramirokejimif.pdfIn PDF document text
    • http://andlupa.com/userfiles/file/29178416865.pdfIn PDF document text
    • http://kirks-pool.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c9eea4aa945---92961087631.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_off0000eabd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEABD 10964 bytes
SHA-256: 1c23c74b05f986b0fc789ec5c69aa1fc9a3250ce0e3a1eb3c318370619b0742d
font_01_sfnt_off0001041c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1041C 16800 bytes
SHA-256: 47de83efdf33e0e8dc869448e7d76e77314c0bbf0d0236d796a4c6397df8f704
font_02_sfnt_off00012fd8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12FD8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1