Malicious PDF — malware analysis report

Static analysis result for SHA-256 b443941427e405d1…

MALICIOUS

PDF

71.9 KB Created: 2021-09-20 00:50:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: df61db29f255c6be993cdf6b70f6f5dc SHA-1: 2255a4845987bbbcda2fc65fef3cf38e8e55ddf7 SHA-256: b443941427e405d1f3a6fd8a5e1d59db31d39a8de9dba8b20a96e368dee93e2d
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains embedded JavaScript and a significant number of external URIs, many of which are hosted on disposable domains. The ML classifier and ClamAV detection strongly indicate malicious intent. The embedded JavaScript likely facilitates the redirection to these external sites, which are characteristic of phishing or malware distribution campaigns.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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
  • 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 https://crysiq.ru/uplcv?utm_term=instagram+download+app+for+android+apk PDF link annotation
    • https://rougezenekar.hu/files/file/zuladen.pdfIn PDF document text
    • https://xpress2.eu/ckfinder/userfiles/files/84415353703.pdfIn PDF document text
    • http://appextskihjthj.handysociality.com/upload/files/jivuvususawenusaza.pdfIn PDF document text
    • https://gbp.dropship-online.com/userfiles/files/57711467843.pdfIn PDF document text
    • https://trucraftsmanship.com/wp-content/plugins/formcraft/file-upload/server/content/files/16138cc7d6a599---pebegapotipufe.pdfIn PDF document text
    • http://sonsuadogo.org/Images_upload/files/rosotugumej.pdfIn PDF document text
    • http://fitsiluet.cz/data/file/pusofibuvotaxamizage.pdfIn PDF document text
    • https://inunekocp.jp/mailmagazine/upload/files/95839345015.pdfIn PDF document text
    • http://3suntech.com/UploadFile/file/20210912232300762.pdfIn PDF document text
    • http://jamalcar.com/userfiles/file/73446373112.pdfIn PDF document text
    • https://leonardscopysystems.com/home/leonards/public_html/ckfinder/userfiles/files/53349211024.pdfIn PDF document text
    • http://tlxzkj.com/uploads/file/0714164068.pdfIn PDF document text
    • http://tecs4.com/intranet/ckfinder/userfiles/files/39717330399.pdfIn PDF document text
    • http://battlegrouponline.com/app/webroot/js/ckfinder/userfiles/files/nevikaviwuresonuzi.pdfIn PDF document text
    • http://1000projects.ru/upload_picture/file/73111940536.pdfIn PDF document text
    • http://silverk.ru/img/lib/file/94049700552.pdfIn PDF document text
    • http://boras-sjuharad.boj.se/uploads/userfiles/files/fixuwaniwagag.pdfIn PDF document text
    • http://koreaseals.com/ckfinder/userfiles/files/vokajiwolag.pdfIn PDF document text
    • http://e-district.org/userfiles/file/60175968836.pdfIn PDF document text
    • https://spirit-legend-enterprises.com/webroot/editor-uploads/files/74669110534.pdfIn PDF document text
    • http://studiophotosfashion.it/userfiles/files/51818982076.pdfIn PDF document text
    • https://magyar-logyogyasz.hu/fileok/file/siwegowatibisuso.pdfIn PDF document text
    • http://hiredriver.com/uploads/assets/files/pavuke.pdfIn PDF document text
    • http://ellenia3.eu/userfiles/files/1985715980.pdfIn PDF document text
    • http://daltan.hu/userfiles/file/mafugogid.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_off0000b72d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB72D 10840 bytes
SHA-256: 3df750590a842e3da26a192fd55f11fc7cbd89f811080aa3a3691990b2a2b95e
font_01_sfnt_off0000cff6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCFF6 16472 bytes
SHA-256: 259d52f68ac578d4ec1b86403b0fb6cdd2e5dbded7acbf0df5f046d28d2a8c4a
font_02_sfnt_off0000f9f1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF9F1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1