Malicious PDF — malware analysis report

Static analysis result for SHA-256 900419b43356c9a3…

MALICIOUS

PDF

94.5 KB Created: 2021-06-28 13:18:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: bb2bb318cea5cdc8b7b716231d9e4ade SHA-1: 50431c1d2fb3c410035e38e702651e22be751908 SHA-256: 900419b43356c9a3fdf73b9dd8c1703fd20db8bfb9c91ed168d85531b60d478b
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and multiple external URIs, many of which point to compromised WordPress sites or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. The embedded JavaScript is likely used to facilitate the redirection or exploit vulnerabilities.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://global-insurance-broker.de/downloads/vuxedokalasemilupobuka.pdf
    • http://www.kliningstroy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160a7f6edb8b84---23676437585.pdf
    • https://ecobox.eng.br/wp-content/plugins/super-forms/uploads/php/files/v170aagiv0j3prsq7j6khg8n3e/resagifatovozorap.pdf
    • http://ecohost.ru/pics/images/file/12273627202.pdf
    • http://africansafaris-spain.com/FCKeditor/editor/filemanager/connectors/php/connector.php?Command=FileUpload&Type=File&CurrentFolder=%2Ffile/riwalezatut.pdf
    • https://glbtrader.com/userfiles/file/27521299329.pdf
    • https://cursosgratuitosonline.es/wp-content/plugins/super-forms/uploads/php/files/neoc4v4aubq8beie4n15103jjg/71561872782.pdf
    • https://xn--arbeitskndigungsrecht-best-5zc.de/userfiles/file/32195989196.pdf
    • http://coimbra.hu/uploads/ckfinder/userfiles/files/lukasefowixusog.pdf
    • http://webscape.co.bw/wp-content/plugins/formcraft/file-upload/server/content/files/1606e9610d1e56---kinuxifosotiz.pdf
    • http://j-club.eu/userfiles/file/40290566187.pdf
    • http://sarljarry.fr/userfiles/file/11180044393.pdf
    • https://bursaceviritercume.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608544ffe8072---xosusosikarof.pdf
    • http://myshopekerala.com/userfiles/file/wajamigifutoxoxusubisix.pdf
    • http://bendhorseride.com/userfiles/file/61432601720.pdf
    • http://grandrosso.com/js/upload/files/xujoj.pdf
    • http://www.hkqi.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ced6e350fa9---wafolifak.pdf
    • https://jfefood.com/wp-content/plugins/super-forms/uploads/php/files/be9a30cf794e38c11b54c9b49ca66421/16931303188.pdf
    • https://maxim-catering.de/wp-content/plugins/super-forms/uploads/php/files/v74ubkl0qnv7fr57jnkos1so8c/jivane.pdf
    • https://storage-in-motion.com/wp-content/plugins/formcraft/file-upload/server/content/files/16071c09eda7fd---nepegizijaf.pdf
    • https://mattweidnerlaw.com/wp-content/plugins/formcraft/file-upload/server/content/files/160892793cfeb9---9303600057.pdf
    • https://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/160cba7c215401---57977324219.pdf
    • https://k2salight.com/wp-content/plugins/super-forms/uploads/php/files/355130fa0b76c539f4d73e3de0c2b5ae/9875986884.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3vuEKuznOb8/uplcv?utm_term=office+2010+professional+activation+key
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00010cf5.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10CF5 16792 bytes
font_01_sfnt_off0001250c.bin
4cab9a36a88322c1fcbacfc7ab3a7e3540c3ac5d66e20f793d7a4a911d526752
pdf-font-stream PDF embedded font (sfnt) at offset 0x1250C 11064 bytes
font_02_sfnt_off00013f19.bin
6fda7b4eda98aed29135020d6ba1b258e12293e84d61050e68846d68392383d5
pdf-font-stream PDF embedded font (sfnt) at offset 0x13F19 17460 bytes