Malicious PDF — malware analysis report

Static analysis result for SHA-256 769ef4138c8083d5…

MALICIOUS

PDF

75.3 KB Created: 2021-09-26 02:30:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 88681d68d7a774ff3ed8cdf7892d0889 SHA-1: 5223c61dee5bf6cdb7a3ea14e15fcbcb2aa65484 SHA-256: 769ef4138c8083d5e237aa9c5ff18b868e035fd966556a23eb77b0f90fa771f3
126 Risk Score

Malware Insights

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

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs, many of which point to disposable domains and are structured as a link farm, a common tactic for phishing or distributing further malware. The document body is heavily obfuscated, preventing a clear understanding of its specific lure, but the overall structure and heuristic firings strongly suggest malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9840

Heuristics 5

  • 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.
  • 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://pnlestari.com/visitbali/image/files/81998821261.pdf In PDF document text
    • http://benhvienlaptop.biz/userfiles/file/lutugu.pdfIn PDF document text
    • http://horizonpestservices.com/userfile/86684237787.pdfIn PDF document text
    • http://thienminhgroup.com/uploads/userfiles/file/rilik.pdfIn PDF document text
    • https://bhiringisamsankalimandir.org/ckfinder/userfiles/files/nakosuno.pdfIn PDF document text
    • https://texigo.tw/upfile/files/2021/09/16/81671780440.pdfIn PDF document text
    • https://fptica.ru/images/file/21298085809.pdfIn PDF document text
    • http://xn--b1afklwjc5g.xn--p1ai/ckfinder/userfiles/files/77437380530.pdfIn PDF document text
    • http://hanleyresources.com/images/3203200261.pdfIn PDF document text
    • http://mdtrend.hu/files/file/xagaripuwarezubo.pdfIn PDF document text
    • http://9meclinic.com/ckfinder/userfiles/files/28406843341.pdfIn PDF document text
    • https://chambredhotes-savoie.com/ckfinder/userfiles/files/31466216188.pdfIn PDF document text
    • http://raylutickenterprises.com/userfiles/files/42313034771.pdfIn PDF document text
    • http://gzafjc.com/uploadfile/files/jetowozoxonumusasikugot.pdfIn PDF document text
    • http://timebymtm.com/upload/files/loserikojev.pdfIn PDF document text
    • https://ymy-tea.tw/upload/files/99637194971.pdfIn PDF document text
    • https://smoothnomad.com/wp-content/plugins/super-forms/uploads/php/files/i939fdl03avefvlonnjn41dv6p/sazupit.pdfIn PDF document text
    • http://ecohort.com/userfiles/files/42856114439.pdfIn PDF document text
    • http://cecev.com/stockages/files/fawurat.pdfIn PDF document text
    • http://krevue.cz/UserFiles/File/87282145365.pdfIn PDF document text
    • https://bodymason.com/user_uploads/files/vabepufakekixedodafunudij.pdfIn PDF document text
    • https://serviceelectric.ca/userfiles/file/wipofewubaroritisexefuma.pdfIn PDF document text
    • https://www.displaysdirectaustralia.com.au/application/third_party/ckfinder/userfiles/files/masuzisikake.pdfIn PDF document text
    • https://408of53crownstreet.com/assets/media/files/gomewosagur.pdfIn PDF document text
    • http://vitcongiong.com/uploads/files/vazofape.pdfIn PDF document text
    • http://recviem.ru/img/upload/51361193043.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/LPIa9PGmDLg/uplcv?utm_term=harry+potter+deathly+hallows+part+1+123moviesPDF 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_off0000b757.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB757 21112 bytes
SHA-256: 001cc2319f306653455de8d250ac3aaf1de0c7b6385c5c7638da4ec6a4751151
font_01_sfnt_off0000ecfb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xECFB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010512.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10512 11152 bytes
SHA-256: 02d624ea461c3e4ed69378a285774d64762caaba5b71d0a75ca1e42fa464825b