Malicious PDF — malware analysis report

Static analysis result for SHA-256 5cfca424c2787999…

MALICIOUS

PDF

64.1 KB Created: 2021-06-24 21:58:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 7b1fa506546cbcdd776f5d1ab30c2cd2 SHA-1: 1941da969dfddc0bff19f6810b0ccfcc705e63d0 SHA-256: 5cfca424c2787999d9d92d146642e6afb98137a09349a3cf6f70f5f8767bd49a
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous external URIs, many pointing to compromised CMS upload storage or disposable hosting, suggesting a link farm designed to redirect users to malicious content. The presence of embedded URLs and the nature of the heuristics strongly suggest this document is part of a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 6

  • 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.
  • 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://krisoc.ru/uplcv?utm_term=din+1142+pdf
    • https://dedywiredja.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a928b15b5ab---8329786360.pdf
    • http://edanieltour.com/FileData/ckfinder/files/20210620_EC7BC81C795F6202.pdf
    • https://hpx.com.ua/wp-content/plugins/super-forms/uploads/php/files/fb549d06f7247c28e1e3df872d40006e/49742350254.pdf
    • https://outsourcedbackoffice.co.uk/wp-content/plugins/super-forms/uploads/php/files/2d68c9e02241626d784e8b77c77cf9ec/4364495673.pdf
    • http://creativeindustries.ru/uploads/userfiles/file/2032561241.pdf
    • http://www.brennholz-heinlein.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607067c68b109---jubimigizeg.pdf
    • http://amirafouad.com/uploaded_files/file/89031976683.pdf
    • https://www.rockandroll.blog.br/wp-content/plugins/super-forms/uploads/php/files/nl9rqetf3e00iijg8vdddkmh1r/39734025916.pdf
    • http://wearefamilypalestine.com/clients/3/3b/3bc38fc23f9ffb54b20226cbd6ad6ce3/File/50923745854.pdf
    • http://www.iamgoingto1996.com/wp-content/plugins/formcraft/file-upload/server/content/files/16097cf0229a58---botanidokulezake.pdf
    • http://skuplaptop.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160a96c9428218---nitagelewofup.pdf
    • http://ciaooo.ru/uploades/userfiles/file/rutizixokojitosokuj.pdf
    • https://coil.hk/upload/files/10750470483.pdf
    • http://subventionsbetrug.de/wp-content/plugins/super-forms/uploads/php/files/7a7grh62gsfdmsm2cbc7vmps1k/30343519345.pdf
    • https://sealskinz.ru/files/file/pomuwizokajevidanuvolof.pdf
    • https://braviengenharia.com.br/wp-content/plugins/super-forms/uploads/php/files/jk6nduiaiaooqat9v3ubhi6dm4/kezarawedidoxopugaseb.pdf
    • http://andreevmag.com/wp-content/plugins/super-forms/uploads/php/files/a97054dcdd6f70b9778a5788048c5510/guvevopugavudonamobarukez.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000b70a.bin
dc8c2f85431d50dfb3bb41f5fd6c64ffcc5b94bfe89427e5d7740651d28b7f65
pdf-font-stream PDF embedded font (sfnt) at offset 0xB70A 4792 bytes
font_01_sfnt_off0000c786.bin
098c935b133c75ec96de2dde125de49791ff17e5dfeb7f862699913a6d6b6200
pdf-font-stream PDF embedded font (sfnt) at offset 0xC786 14424 bytes