Malicious PDF — malware analysis report

Static analysis result for SHA-256 164147bf1dbd5a4a…

MALICIOUS

PDF

74.9 KB Created: 2021-09-15 21:10:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 96876163e0fca4840574b6911001692b SHA-1: 8f247a3c66dd3997bc328c90ac130cbef76a294d SHA-256: 164147bf1dbd5a4ab5d13cadc375e4bb564f124abb823efbd694e8ec5d549eba
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs and is flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a large number of links to potentially disposable hosting, suggesting an attempt to distribute malicious content or phish users. No scripts were extracted, but the presence of many external links points to a lure mechanism.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

Heuristics 5

  • 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.
  • 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://krisoc.ru/uplcv?utm_term=comment+synchroniser+agenda+outlook+et+android PDF link annotation
    • http://www.morrisjones.co.uk/EditorImages/file/farujenovimolebevokope.pdfIn PDF document text
    • http://99hospitalitygroup.com/ckfinder/userfiles/files/getodelosederirimuro.pdfIn PDF document text
    • http://sevoir.hu/uploads/file/xulekuvevex.pdfIn PDF document text
    • https://yellowmangocafe.com/userfiles/file/nexapugalumifugu.pdfIn PDF document text
    • http://portalpr-b2b.es/img/user//file/_0919762001631365571.pdfIn PDF document text
    • http://rockycheng.com/ckfinder/userfiles/files/puvazalokisetumisopa.pdfIn PDF document text
    • http://www.sunaryem.com.tr/wp-content/plugins/super-forms/uploads/php/files/ror7dke6l493rksm4rv6rvg6m5/vomixozetenibowaxafela.pdfIn PDF document text
    • https://naveenent.com/administrator/imagetemp/file/69407246498.pdfIn PDF document text
    • http://antonioruizabogados.es/userfiles/file/2548442490.pdfIn PDF document text
    • https://textosolutionslinguistiques.com/upload/editor/file/guzuzex.pdfIn PDF document text
    • http://www.mmd.ntou.edu.tw/ckfinder/userfiles/files/15315064758.pdfIn PDF document text
    • http://galsabino.it/userfiles/files/mofetagej.pdfIn PDF document text
    • http://dinskayarealty.ru/media/file/suzodaje.pdfIn PDF document text
    • https://888nv.ru/userfiles/file/xugedulesuzumudasopim.pdfIn PDF document text
    • https://rcvizovice.cz/ckfinder/userfiles/files/29015128556.pdfIn PDF document text
    • http://maychamsocda.vn/images/userfiles/file/52510551154.pdfIn PDF document text
    • https://valerart.com/ckfinder/userfiles/files/72558308958.pdfIn PDF document text
    • http://geoplan.su/userfiles/file/87072342596.pdfIn PDF document text
    • http://3wsystems.com/shipinc/userfiles/files/52038114468.pdfIn PDF document text
    • https://sirikulsteel.com/wp-content/plugins/formcraft/file-upload/server/content/files/16141b87baa659---33764249346.pdfIn PDF document text
    • http://alexlunacoach.com/img/editor/file/wovozu.pdfIn PDF document text
    • https://santchavarabed.in/ckfinder/userfiles/files/34742584910.pdfIn PDF document text
    • http://sergeisurzhin.ru/ckfinder/userfiles/files/7197857850.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_off0000bfb8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBFB8 11156 bytes
SHA-256: d1c2ec8757a701fa651377727157fb1abfb70690b5be74753d8a28075bd068f7
font_01_sfnt_off0000d974.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD974 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f186.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF186 17212 bytes
SHA-256: 1936a86984f9f61542540d9cdc746f868a7c4c987465f36adb833731464a0c96