Malicious PDF — malware analysis report

Static analysis result for SHA-256 bef1eb2f21ceae87…

MALICIOUS

PDF

76.6 KB Created: 2021-09-23 18:50:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: fa5fbc4afa182e5c1980ee02703c24d5 SHA-1: f481926e0a6a6ea334bf5691e3be86bd49242b17 SHA-256: bef1eb2f21ceae87eae0283389639181746a7a46584a87627e062583bb70f72e
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by multiple heuristics, including a critical ClamAV detection and an ML classifier, indicating malicious content. The presence of numerous external URIs, many pointing to disposable hosting and acting as link farms, suggests a phishing or malware distribution attempt. The document body is heavily obfuscated, but the overall structure and heuristic firings strongly indicate a malicious intent to redirect users to harmful websites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://oniceh.ru/uplcv?utm_term=android+6.0+1+marshmallow+rom+zip PDF link annotation
    • https://webrekruit.com/php_codes/Scott/VieauAssociates/code/userfiles/file/geratariwunepovudig.pdfIn PDF document text
    • http://dsacare.com/admin/uploads/file/95815240027.pdfIn PDF document text
    • http://1544-7419.net/upload/fckeditor/file/zutaxugudosapagojebajep.pdfIn PDF document text
    • http://www.heksan.com.pl/file/4604668215.pdfIn PDF document text
    • http://dulichtantai.com/files/uploaded/files/92577219408.pdfIn PDF document text
    • http://santeh.md/img/files/ruvatuwerofitugobogapufi.pdfIn PDF document text
    • http://www.bongbansaigon.com/uploads/files/81316463092.pdfIn PDF document text
    • http://mabo-meccanica.eu/userfiles/files/wovirejubolefixiwos.pdfIn PDF document text
    • http://safarekhoob.ir/basefile/safarekhoobir/files/16568963004.pdfIn PDF document text
    • http://carnavaldemarbella.com/Senegal_5/Content/files/userfiles/file/kozajow.pdfIn PDF document text
    • http://scpt.it/userfiles/files/lajivotuwige.pdfIn PDF document text
    • http://mygiftltd.com/userfiles/file/58909092886.pdfIn PDF document text
    • https://www.puskinas.lt/ckfinder/userfiles/files/30671241766.pdfIn PDF document text
    • http://salwex.hu/file/52792793464.pdfIn PDF document text
    • http://abworder.com/uploads/files/30634108421.pdfIn PDF document text
    • http://surausa.com/uploads/files/37357143576.pdfIn PDF document text
    • http://sochi-riba.ru/ckfinder/userfiles/files/bozifox.pdfIn PDF document text
    • http://raduzhniy.com/wp-content/plugins/formcraft/file-upload/server/content/files/161418e9aa1457---wosigogoronusatuv.pdfIn PDF document text
    • https://birotex.rs/images/files/fikedoxuxujeturunapikaj.pdfIn PDF document text
    • http://akatumusics-ang.communication-pro.fr/public/1283/contenu/file/zujoperupekoze.pdfIn PDF document text
    • http://kaie.org/userfiles/file/20210918190929.pdfIn PDF document text
    • http://ghibms.com/userfiles/files/28881603196.pdfIn PDF document text
    • http://saringkarnwood.com/UserFiles/file/gavoma.pdfIn PDF document text
    • https://harrisitalia.it/uploads/file/61135457088.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_off0000c53b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC53B 17776 bytes
SHA-256: 8c472fc2923eb33c8d5e6995fa92b13b4578652c82cef45b8ae780411cf8d1b6
font_01_sfnt_off0000f33c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF33C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010b53.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10B53 10964 bytes
SHA-256: 30d0bd3d1358d7e7955483951aaa8b08b8cfa250f7b2e5891ef2a26bd536cb6f