Malicious PDF — malware analysis report

Static analysis result for SHA-256 31f18e54adef213a…

MALICIOUS

PDF

83.9 KB Created: 2021-10-21 16:11:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: a68a9bb509f53133ee55ac618ce62c50 SHA-1: 8848e145dba113575770ce4e9e047bb8b849f2be SHA-256: 31f18e54adef213a861fc7b74c1ddd088917bfa121ad91fd8539cca2b42f7cca
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The ML classifier and ClamAV detection strongly indicate malicious intent. The PDF contains numerous embedded URLs, many pointing to disposable domains, suggesting a link farm or phishing lure. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' confirms this, indicating the PDF is designed to redirect users to a large number of distinct, potentially malicious, hosts.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://learningsolution.ca/userfiles/files/85613454591.pdf In PDF document text
    • http://s-pack.kr/userfiles/file/20211006081701.pdfIn PDF document text
    • http://ylgems.com/file_media/file_image/file/nojubosevitej.pdfIn PDF document text
    • https://togelunited4d.com/contents/files/jojepaxakejolo.pdfIn PDF document text
    • https://cicasoftavukatwebsitesi.demowebsiteleri.com/upload/files/nokolegikazopu.pdfIn PDF document text
    • https://stockbauer.hu/uploads/file/92365050285.pdfIn PDF document text
    • http://radtel-sport.pl/userfiles/file/75724464102.pdfIn PDF document text
    • http://anneadamslaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/50288800291.pdfIn PDF document text
    • http://solarexperte.ch/fckeditor/editor/images/file/64183570122.pdfIn PDF document text
    • http://harekatmemuru.com/images/Media/files/wafoxitotodiresuv.pdfIn PDF document text
    • http://whygzy.com/Media/Uploads/files/zezawuvokis.pdfIn PDF document text
    • https://phunhai.net/upload/files/kilelisilesepiw.pdfIn PDF document text
    • http://ghettaetamionarchitetti.it/userfiles/files/12107712052.pdfIn PDF document text
    • http://neoneofitou.com/ckfinder/userfiles/files/xuxojufasurisikilab.pdfIn PDF document text
    • http://instit.ac/ckfinder/userfiles/files/97069984770.pdfIn PDF document text
    • https://sodigital.it/wp-content/plugins/formcraft/file-upload/server/content/files/16135cef0eedce---sironavunoro.pdfIn PDF document text
    • https://saleskerala.com/ckfinder/userfiles/files/33658116866.pdfIn PDF document text
    • https://itracmediav5.com/ckfinder/userfiles/files/muvovajinizuduk.pdfIn PDF document text
    • http://balcimimarlik.com/resimler/files/64454692381.pdfIn PDF document text
    • https://encouragingmath.com/wp-content/plugins/super-forms/uploads/php/files/9a5ac5f667c4f22e3dce5a55147bd92c/xexiludazalaleleremu.pdfIn PDF document text
    • https://natyabio.com/uploadfiles/62348432828.pdfIn PDF document text
    • https://harom.ro/files/file/pefakizakosogevazozegus.pdfIn PDF document text
    • http://vuoncotichdep.com/upload/files/80246623492.pdfIn PDF document text
    • http://gsnursing.in/ckeditor/ckfinder/userfiles/files/nanuxepemupuzizurexujib.pdfIn PDF document text
    • http://rimini-portal.de/bilderarchiv/file/lovataguguxevapoz.pdfIn PDF document text
    • http://feedproxy.google.com/~r/MbOu/~3/7xhmvLXWVJc/uplcv?utm_term=list+of+flute+playersPDF 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_off0000e5da.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE5DA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000fdec.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFDEC 17192 bytes
SHA-256: ccd6a4d20b7afc0fdbf8f3a538478eece06a0ece888008f9b5d2ba714e7a8c62
font_02_sfnt_off00012a1e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12A1E 10416 bytes
SHA-256: a55b99254540431b21683178eac157d8f7306d712a76c39591fa1b8d5805b128