Malicious PDF — malware analysis report

Static analysis result for SHA-256 9b786c0aec3d704b…

MALICIOUS

PDF

82.9 KB Created: 2021-09-19 04:46:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 3c47852697e9f74b02e733108ef19181 SHA-1: 35a61af90dfacc75bdf8067b9a7e9ad99e4bdd9c SHA-256: 9b786c0aec3d704b948a16488589dab1466e785b69e93817afea184ee84b4f88
166 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The sample was flagged by ML classifiers and ClamAV as malicious, with heuristics indicating a social-engineering lure to install a browser extension or update. The document body is heavily obfuscated, but the presence of numerous external links and the 'SE_BROWSER_INSTALL_LURE' heuristic strongly suggest a phishing or malware distribution attempt. The numerous unknown URLs likely serve as landing pages for the malicious payload.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

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
  • Browser extension / update installation lure high SE_BROWSER_INSTALL_LURE
    Document tells the user to install a browser extension, plugin, viewer, or browser update to view content — a common social-engineering path for credential theft and malware installation
  • 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://nifaelectronics.com/userfiles/file/49195724642.pdf In PDF document text
    • https://workinhotel.com/upload/fckfile/xowemotogusodanusar.pdfIn PDF document text
    • http://nayyaralidada.com/alpha/ckfinder/userfiles/files/xenafakiwonejopatetupepes.pdfIn PDF document text
    • https://concertwristband.com/resimler/files/loxorekezoxeguvagiti.pdfIn PDF document text
    • https://cuacuonbentre.com/upload/files/19477543164.pdfIn PDF document text
    • http://www.propper-droppers.nl/files/file/35692750956.pdfIn PDF document text
    • http://bora.su/ckfinder/userfiles/files/supesowagiwirun.pdfIn PDF document text
    • https://thefertilizerproductionline.com/d/files/94954214071.pdfIn PDF document text
    • http://sanarina.de/ckfinder/userfiles/files/nojixekedavowuj.pdfIn PDF document text
    • https://www.pharmaright.ca/wp-content/plugins/super-forms/uploads/php/files/g05ma0311rs4er8ljl2tgkg1u3/44016417227.pdfIn PDF document text
    • http://imhyuk.com/imhyukeditor/userfile/file/baweburoditifen.pdfIn PDF document text
    • http://opuspointpartners.com/ckfinder/userfiles/files/rusegijasisirigepeluj.pdfIn PDF document text
    • https://pmcp-avac.com/files/upload-ckfinder/files/62510894179.pdfIn PDF document text
    • https://migger.dk/userimages/file/mafamaxalisaw.pdfIn PDF document text
    • http://facilitymanagementassociates.com/survey/userfiles/files/66505453556.pdfIn PDF document text
    • http://bc-arman.kz/ckfinder/userfiles/files/pisasunej.pdfIn PDF document text
    • http://metallpress.info/files/xipepuribidupup.pdfIn PDF document text
    • http://ubest.ru/images/file/60744954361.pdfIn PDF document text
    • http://isdoor.ru/uploads/files/rutemutibuziva.pdfIn PDF document text
    • https://www.clubmanizales.com.co/wp-content/plugins/formcraft/file-upload/server/content/files/16130c989dc33a---jekojelaf.pdfIn PDF document text
    • https://takipcisec.com/calisma2/files/uploads/31218548158.pdfIn PDF document text
    • https://dreptultau.hotnews.md/upload/userfiles/files/wifeminikutesenet.pdfIn PDF document text
    • http://www.prunay-en-yvelines.fr/ckfinder/userfiles/files/nuzunaviwilunolezabumomor.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/LPIa9PGmDLg/uplcv?utm_term=messenger+crashing+androidPDF 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_off0000dfb0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDFB0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f7c2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF7C2 17988 bytes
SHA-256: d14871deb82b534edf5a864fa178711dedc3a6ca06732d39eedb0c6d97899b19
font_02_sfnt_off00012691.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12691 10500 bytes
SHA-256: cecbfb9176cc548a8f35ebe88191553ba864f01e6d656bdd0f1f8b277223e37e