Malicious PDF — malware analysis report

Static analysis result for SHA-256 ef876da01d1e6df0…

MALICIOUS

PDF

88.8 KB Created: 2021-09-15 12:29:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 70b900967a6f070148b8071bdf769862 SHA-1: a64e84810b6600181340747a8fee8b49e2a3c7c9 SHA-256: ef876da01d1e6df0d1190c215c72cc3ff13fb838ea1dd56ca2aa98e4fa358f24
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.001 User Execution: Malicious Link

The PDF contains a link farm pointing to multiple compromised websites and disposable hosting, indicating a phishing or malware distribution attempt. The ML classifier and ClamAV detection strongly suggest malicious intent. The document body is unreadable, but the heuristics and URLs confirm the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9822

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 http://musikpark-live.de/userfiles/file/dasenabu.pdf In PDF document text
    • http://agedwedfjtj.pretty-match.com/upload/files/66344666206.pdfIn PDF document text
    • https://wamsconference.com/wp-content/plugins/super-forms/uploads/php/files/2e385bbab31abb2034d58d5b2adca058/nigajinapob.pdfIn PDF document text
    • http://uitetenindex.nl/images/uploads/ruxukexo.pdfIn PDF document text
    • https://shieldtech.cz/ckfinder/userfiles/files/36145048036.pdfIn PDF document text
    • https://parquesanalbertohurtado.cl/ckfinder/userfiles/files/99893101692.pdfIn PDF document text
    • https://lorenzonimmigrationlaw.com/wp-content/plugins/formcraft/file-upload/server/content/files/161306c940b46d---takowejovujamu.pdfIn PDF document text
    • http://stroynerud-sm.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1613508616f86b---41623945666.pdfIn PDF document text
    • http://sieuthivatlieuhoanthien.com/upload/files/jonububunadelez.pdfIn PDF document text
    • http://luisacortesearchitetto.it/userfiles/files/76698024003.pdfIn PDF document text
    • http://dc-3ed4d7413bdb.prshots.de/uploads/userfiles/1630749801/files/88678918293.pdfIn PDF document text
    • https://sharkovinkom.com/sharkovinkom.com/ckfinder/userfiles/files/gemegirififonopod.pdfIn PDF document text
    • http://elfast.ru/userfiles/file/7460752068.pdfIn PDF document text
    • http://ned.ru/uploads/files/jatelawiserop.pdfIn PDF document text
    • http://autobedrijvenindex.nl/images/uploads/48025369726.pdfIn PDF document text
    • http://georgewongdesign.com/gwd/upload/files/gapikubajofipilot.pdfIn PDF document text
    • http://hakanhurdacilik.com/userfiles/file/99904177205.pdfIn PDF document text
    • http://www.ville-dammarie.com/ckfinder/userfiles/files/nulevegobisuxi.pdfIn PDF document text
    • http://nigerseedindia.com/uploads/72863003197.pdfIn PDF document text
    • https://iphonerepairservice.nl/app/webroot/files/userfiles/files/juxitovodokoluwasosilod.pdfIn PDF document text
    • http://avsa.org/sites/default/files/images/files/papakar.pdfIn PDF document text
    • http://pololanna.com/user_img/files/19472999964.pdfIn PDF document text
    • https://euroroma-bg.org/files/file/badegegafis.pdfIn PDF document text
    • http://cathugo.de/res/wysiwyg/file/rutaxaruwewa.pdfIn PDF document text
    • http://www.contectrade.hu/fckfiles/file/37090314312.pdfIn PDF document text
    • http://studiofantino.it/userfiles/files/31654343427.pdfIn PDF document text
    • http://epmachine.ru/d/files/6037711229.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BkSY9tpko7c/uplcv?utm_term=android+flash+porn+gamesPDF link annotation
    • 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_off0000f7ca.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF7CA 17592 bytes
SHA-256: 7ab750389b860c5740be5cb0b54fb9e4cf603bd3b833893a278987e0b4e5f3bd
font_01_sfnt_off00012551.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12551 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00013d68.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13D68 10828 bytes
SHA-256: cc7164d54e7d3c1e8c883c70e0d5aa13464463d0c27b57517e9281d1a52a699c