Malicious PDF — malware analysis report

Static analysis result for SHA-256 3715b7aaa9e97b24…

MALICIOUS

PDF

69.9 KB Created: 2021-09-27 09:32:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 024cf8be851ccd5857d69e58c3dedc2f SHA-1: ccaf4ea8b55879a752d5f814a5505bc4f1535b67 SHA-256: 3715b7aaa9e97b24b225ebe974e2c98ff87e08bd447a356136cb88be570d4128
156 Risk Score

Malware Insights

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

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, directing users to multiple external URLs, some hosted on compromised WordPress sites. The embedded URLs and the nature of the link farm suggest an attempt to redirect users to malicious content or phishing pages.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9982

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 http://czechnews.cz/userfiles/files/zewurokovadorexelafadarav.pdf In PDF document text
    • https://joinvita.com/neu/userfiles/file/labidiwa.pdfIn PDF document text
    • http://levant-tekstil.com/other_files/File/93236494208.pdfIn PDF document text
    • https://tl-systems.hu/files/files/gemusu.pdfIn PDF document text
    • http://innobiztour.com/FileData/ckfinder/files/20210908_E949A8BE1188668F.pdfIn PDF document text
    • http://self119.net/upload/userfiles/2021/09/files/210927124236.pdfIn PDF document text
    • http://aelma.com/sites/default/userfiles/file/93573053311.pdfIn PDF document text
    • https://open-call.fr/uploaded/files/luzokobipasesunuvadusez.pdfIn PDF document text
    • https://brokenspoke.com/wp-content/plugins/super-forms/uploads/php/files/7d28ddd7d9816e714f0efc8607c7b29b/kukomep.pdfIn PDF document text
    • https://www.tifdip.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613b1b65137be---4171158487.pdfIn PDF document text
    • http://emilymillerlaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/kijigujewun.pdfIn PDF document text
    • http://creptiles.dk/userfiles/file/15301474891.pdfIn PDF document text
    • http://lirealestatelitigator.com/wp-content/plugins/super-forms/uploads/php/files/32df833c16e46ac1a13365c986f5dd30/magunovimekaxejazefaz.pdfIn PDF document text
    • https://martan.es/cenavarra_userfiles/files/8466316596.pdfIn PDF document text
    • http://www.siposferenc.hu/html/14459248680.pdfIn PDF document text
    • http://www.guaitoli.eng.br/wp-content/plugins/formcraft/file-upload/server/content/files/1614b7ec3b3ce9---1211962983.pdfIn PDF document text
    • http://pieseclimaauto.com/files/file/1615754359.pdfIn PDF document text
    • http://penzionnakrizankach.cz/ckfinder/userfiles/files/35945662345.pdfIn PDF document text
    • http://claudiamelchior.it/images/file/84550090399.pdfIn PDF document text
    • http://lagostena.it/userfiles/files/40841494119.pdfIn PDF document text
    • http://prota.ru/upload/files/59823248721.pdfIn PDF document text
    • http://cosmosimpex.com/app/webroot/ckfinder/userfiles/files/8129618319.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/zMnd8XtcwSM/uplcv?utm_term=android+tablet+software+neu+installierenPDF 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_off0000b12c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB12C 15784 bytes
SHA-256: 1add044ac805b0fc410a396effa665ca4eedad8896ce363beaaad8d6619f8fa9
font_01_sfnt_off0000d936.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD936 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f14d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF14D 10652 bytes
SHA-256: 52dee7caccf055edac10783438c87a224fc17f445e220506fd6ea7391fd171df