Malicious PDF — malware analysis report

Static analysis result for SHA-256 63dc72bc92d23146…

MALICIOUS

PDF

86.9 KB Created: 2021-08-05 14:10:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-22
MD5: dc3d28899af18cb1d2749cb99e72d5de SHA-1: 4cdf501eb4d63cc8a40af3cf0b834f0ba32614b2 SHA-256: 63dc72bc92d231462911087cea0fe61a6c9242e2f7224bc6605257a39da7b768
156 Risk Score

Malware Insights

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

This PDF file was identified as malicious by multiple heuristics and a machine learning classifier, with ClamAV detecting it as a phishing trojan. It functions as a link farm, containing numerous URLs that point to compromised WordPress uploads and other disposable hosting, suggesting an attempt to redirect users to malicious sites. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, providing no direct user-facing content but likely serving as a container for the malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

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://wastran.ru/uplcv?utm_term=brain+teasers+worksheets+for+adults+with+answers PDF link annotation
    • https://rivieresoceanie.com/userfiles/file/matulijuvejirupesuneweti.pdfIn PDF document text
    • https://desertflying.club/wp-content/plugins/formcraft/file-upload/server/content/files/160a7abb74a1eb---22478098903.pdfIn PDF document text
    • http://barrarioservicos.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1606f395323e69---sesusanivaruboj.pdfIn PDF document text
    • http://indiebookoftheday.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d1f98f2642---woliki.pdfIn PDF document text
    • http://english-life.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16072000cec3e7---butik.pdfIn PDF document text
    • http://www.sbawerribee.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160edcbb0c4bd2---30056659243.pdfIn PDF document text
    • http://xinyuemu.net/assets/202107/files/20210721170554742092.pdfIn PDF document text
    • http://keralajesuits.org/userfiles/file/41332127833.pdfIn PDF document text
    • https://playerpress.com/ckfinder/userfiles/files/kumoduwalupekujawaja.pdfIn PDF document text
    • https://ksboutlet.com/file/files/zudorinizizunad.pdfIn PDF document text
    • https://www.financedeclined.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160ae6e1b80e32---28005355792.pdfIn PDF document text
    • https://www.westcountrystoves.co.uk/wp-content/plugins/super-forms/uploads/php/files/3646e4efc2a2641911effe7a42aa2220/57225380583.pdfIn PDF document text
    • http://novosib-sport.ru/ckfinder/userfiles/files/44474905367.pdfIn PDF document text
    • http://pilot-market.ru/new/files/file/68296291853.pdfIn PDF document text
    • https://victory-agency.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ade9b9bc6e1---14222154683.pdfIn PDF document text
    • http://www.introspekta.si/ckfinder/ckeditor_uploaded_files/files/nozesemas.pdfIn PDF document text
    • http://cp-tournament.org/ckfinder/userfiles/files/24511880127.pdfIn PDF document text
    • http://neuragen.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160c3853ee32da---55848086534.pdfIn PDF document text
    • http://www.birapart.com/wp-content/plugins/formcraft/file-upload/server/content/files/16087ed3832181---xajixapigujazopetigefuli.pdfIn PDF document text
    • http://askort.pl/Upload/file/wuzizirinuxumufobugo.pdfIn PDF document text
    • https://mygamedaysports.com/wp-content/plugins/super-forms/uploads/php/files/6c0959af9b140f2dc26f1362f39465b1/xaxufig.pdfIn PDF document text
    • https://ruxthai.com/ckfinder/userfiles/files/45361390665.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_off0000ec3e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC3E 10784 bytes
SHA-256: 7746504195cfc76e9ea23ac756d9e2ff8f63f3e66a2e73280b836b50c34170ab
font_01_sfnt_off00010514.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10514 17908 bytes
SHA-256: 0b6504f33c175554041319912c3feed7794f21ddbafa3397f0cbc93cca628721
font_02_sfnt_off000133b9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x133B9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1

Open this report in the interactive analyzer, or submit your own file for analysis.