Malicious PDF — malware analysis report

Static analysis result for SHA-256 5b1d2764d1e0354a…

MALICIOUS

PDF

70.2 KB Created: 2021-06-07 02:59:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-29
MD5: 7498a8217fe7c785c3e3390699fbb17d SHA-1: 5aebc6ad7ad69fe02a9ee6918b20c0c9f71f491a SHA-256: 5b1d2764d1e0354aef223d7edd60233ae60f8fedef108d66e17d94eec15da398
156 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It functions as a link farm, with numerous embedded URLs pointing to compromised WordPress sites and other disposable hosting. These links likely lead to phishing pages or further malware downloads, consistent with a spearphishing attachment attack vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://cructi.ru/uplcv?utm_term=duplicate+cleaner+prime+apk PDF link annotation
    • https://flvirginia.com/wp-content/plugins/super-forms/uploads/php/files/b37382befb32230727b03fe2edbfb211/sakufobabupusufidizelejos.pdfIn PDF document text
    • http://becro-plast.hr/wp-content/plugins/formcraft/file-upload/server/content/files/160a80a6094331---67961692041.pdfIn PDF document text
    • https://whitelightdesign.com/wp-content/plugins/super-forms/uploads/php/files/e43888574b38a818097752c03e5ca7a1/nurebevezivimupuzimem.pdfIn PDF document text
    • https://avis-medical.ma/wp-content/plugins/super-forms/uploads/php/files/bbadb53344e3860f61ddb61294f4747d/78553895701.pdfIn PDF document text
    • https://www.dentaltaxpros.com/wp-content/plugins/super-forms/uploads/php/files/c0bc041d6228f40f972b3473a67bd8e4/befowojufigimiro.pdfIn PDF document text
    • http://pnmanagementsolutions.in/uploads/51097374373.pdfIn PDF document text
    • http://cga82.com/admin/File/dududugopefalebiwebefax.pdfIn PDF document text
    • http://donghozibistore.com/luutru/files/raxodesawezi.pdfIn PDF document text
    • http://eske.hu/wp-content/plugins/formcraft/file-upload/server/content/files/1607dab197a7e6---2498889078.pdfIn PDF document text
    • https://arizonapoolcontractor.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609255c802521---jimuvanajo.pdfIn PDF document text
    • https://asaptransfers.co.uk/wp-content/plugins/super-forms/uploads/php/files/s4h7i4aka1722b3btmqjsfvmr0/vakobegamerufulosi.pdfIn PDF document text
    • http://www.recetasyconsejos.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607bb2968bb24---lenopotadax.pdfIn PDF document text
    • http://fine-cottage.ru/userfiles/file/jurejasozefabezewivevu.pdfIn PDF document text
    • http://hzjksj.com/images/upload/File/38372693419.pdfIn PDF document text
    • https://refour.dk/wp-content/plugins/super-forms/uploads/php/files/541a6d59b9e8709cf12df549b45ac638/newotalupeduveruzinaju.pdfIn PDF document text
    • https://sweetestspaparty.com/wp-content/plugins/formcraft/file-upload/server/content/files/160973be4eec86---minujutosugom.pdfIn PDF document text
    • https://www.ptlittleflower.org/wp-content/plugins/super-forms/uploads/php/files/ec0lpcr1qee2akh52gut80v447/58918540493.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d488.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD488 4964 bytes
SHA-256: 994ca656383a56f1df3adc65546f01a5f12a05c774aa478bcac36d70fea04709
font_01_sfnt_off0000e558.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE558 11240 bytes
SHA-256: 7cb3a39b00b6d9e6b8f7f198a2e3617bf9af9d3d81e1a2d901df2f8bdac34544