Malicious PDF — malware analysis report

Static analysis result for SHA-256 397e524f462801de…

MALICIOUS

PDF

164.3 KB Created: 2021-10-05 04:52:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: f03f5dbdf6a29e74bcb4e86cc682e1d5 SHA-1: 73fe8f8ac36db54b33eeffeedd0a9bedc7892c57 SHA-256: 397e524f462801de000ab48110afa8ce32047cf0e082fb5f9f9d2a42fc35ec0f
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript, which is a common technique for executing malicious code within documents. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates that the PDF contains numerous links to disposable hosting, suggesting a phishing or spam campaign. The ML classifier and ClamAV detection strongly indicate malicious intent. The embedded JavaScript likely redirects the user to one of the numerous external URLs found in the document, which are part of a link farm.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9966

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
  • 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://armature.ir/cache/fck_files/file/14507649692.pdf In PDF document text
    • http://internet-trade.cz/UserFiles/file/resimisiwe.pdfIn PDF document text
    • https://ecableapp.com/FCKeditor/FCKimgUpload/file/kidujesa.pdfIn PDF document text
    • http://nineslash.com/user_file/file/tubifikip.pdfIn PDF document text
    • https://webkapper.nl/ckfinder/userfiles/files/7268031030.pdfIn PDF document text
    • https://joepromenshealth.com/wp-content/plugins/super-forms/uploads/php/files/3f275fbe67b943484fb2e1abf2da4662/57349181897.pdfIn PDF document text
    • http://www.dagmarsvendova.cz/admin/js/ckfinder/userfiles/files/zosesasugililetasesume.pdfIn PDF document text
    • https://eobliecky.sk/userfiles/file/jorividowirejinar.pdfIn PDF document text
    • https://www.clinicaepilepsia.cl/ckfinder/userfiles/files/buwojazefukefe.pdfIn PDF document text
    • http://peneleos.pl/userfiles/file/zebudatagenosawip.pdfIn PDF document text
    • https://sieuthimaytinhcu.vn/upload/files/xexipibo.pdfIn PDF document text
    • https://truckforceone.eu/upload/editor/file/1150496237.pdfIn PDF document text
    • https://tinhhoaxanh.vn/userfiles/file/34626329990.pdfIn PDF document text
    • http://fluitec.fr/ressource/site-image/files/bajabotimezages.pdfIn PDF document text
    • http://robwalker.net/fckupload/file/varaburolo.pdfIn PDF document text
    • https://wotfiles.com/ckfinder/userfiles/files/48393307377.pdfIn PDF document text
    • https://roshnaai.com/ckfinder/userfiles/files/rowujawi.pdfIn PDF document text
    • http://johndanton.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/85740014485.pdfIn PDF document text
    • https://cdmsig2.com/ckfinder/userfiles/files/tegefiminubapilut.pdfIn PDF document text
    • http://paillasse.hu/userfiles/file/85708275378.pdfIn PDF document text
    • http://bctlorraine.org/userfiles/file/netosarokaxigiseru.pdfIn PDF document text
    • https://www.xcelsus.de/wp-content/plugins/formcraft/file-upload/server/content/files/1612fb6cad88c9---13285522139.pdfIn PDF document text
    • http://3bbb.fr/ckeditor/upload/files/xoxexajadepanivaso.pdfIn PDF document text
    • http://flygarfield.net/userfiles/file/wuxaxugakojuwuxexozobiz.pdfIn PDF document text
    • https://acrgruppe.de/userfiles/file/48638628181.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/FevRqgeaUVY/uplcv?utm_term=a+song+of+ice+and+fire+character+illustrationsPDF 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_off000215cf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x215CF 23092 bytes
SHA-256: a07657db9f7c88d6d2544c7d8474cc4fa1db5d862bf4f1cdb80e7671bfcb9bf3
font_01_sfnt_off000251e8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x251E8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000269ff.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x269FF 10836 bytes
SHA-256: 45db9cf785dfa8d1f6e33b316c3350f9542540a5adbee81f6954850a6f741392