Malicious PDF — malware analysis report

Static analysis result for SHA-256 c3533e294d0179c5…

MALICIOUS

PDF

105.5 KB Created: 2021-06-10 04:47:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-27
MD5: 2e405ff076c9f20cfa77d1da19dd3c7d SHA-1: aa228acfea2fd3365b6c7a8b92217d8b413edc45 SHA-256: c3533e294d0179c51ae1f67aa907727e8e3197f483dc4c3f2fc8ac82daa27516
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains numerous external URIs and link farm heuristics, indicating it is designed to redirect users to potentially malicious websites. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. The document body is heavily obfuscated and appears to be junk data, offering no direct clues to the specific lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

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://laborke.ru/uplcv?utm_term=beyblade+burst+season+2+episode+45 PDF link annotation
    • http://nowyhotelik.pl/userfiles/file/10552409490.pdfIn PDF document text
    • https://bruceautoservice.com/files/file/95689503620.pdfIn PDF document text
    • https://alphacleanwashing.com/wp-content/plugins/super-forms/uploads/php/files/77f82dfd9aa54a2950e634df9c6caea3/fevesafegakuz.pdfIn PDF document text
    • https://aduanaldelvalle.com/userfiles/file/tezejojupalubelugikig.pdfIn PDF document text
    • https://cwlighting.com/wp-content/plugins/super-forms/uploads/php/files/b40e1758d362ce6eaec6682d7222caac/29482206205.pdfIn PDF document text
    • https://www.diktu.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a2a9c263b9b---58169423828.pdfIn PDF document text
    • https://goodline.by/userfiles/file/13511221009.pdfIn PDF document text
    • http://www.studiolegalefusimorelli.com/wp-content/plugins/formcraft/file-upload/server/content/files/16074848b05f3d---xupegaralusatu.pdfIn PDF document text
    • https://chefinhogourmet.com/wp-content/plugins/super-forms/uploads/php/files/18d506278b593511d2095ee17bf01503/nixorulon.pdfIn PDF document text
    • https://comesa.com.pe/wp-content/plugins/super-forms/uploads/php/files/pjm73m3hb9bvcrleenb918fn22/kikelutedi.pdfIn PDF document text
    • http://www.aluvascientific.com/UserFiles/file/39594036650.pdfIn PDF document text
    • https://www.elementstraining.co.uk/wp-content/plugins/super-forms/uploads/php/files/5bdpq5fptq9kma3t7f2anbmmhi/sarufejuzex.pdfIn PDF document text
    • https://portsidestrategies.com/wp-content/plugins/super-forms/uploads/php/files/996ff59353c67cb92bd3be3c78f37afc/10848514445.pdfIn PDF document text
    • http://amtusa.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b0042e3d00f---mixovelupegefinudena.pdfIn PDF document text
    • http://www.photobreak.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16085481eaf50b---kitujevenodovizotuvinow.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00013ad4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13AD4 6300 bytes
SHA-256: 77be9eae487988ec93212ce66ef166926070a6aca0b2a14032ed56bc13aaef5e
font_01_sfnt_off00015087.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15087 5472 bytes
SHA-256: 75c7c10199a503dfd66a69743793efaa5777f2b562b135b58d62120073157777
font_02_sfnt_off0001632d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1632D 11860 bytes
SHA-256: b3c772ac86b428346653063c52f25296480b9573eabf23797191ecbe03170ad7
font_03_sfnt_off00018a69.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x18A69 4324 bytes
SHA-256: b50a2106bf82917db0cd3cf88f63c5e8cc3298b343ace5cffc591b35df33d24c