Malicious PDF — malware analysis report

Static analysis result for SHA-256 a3a00990ba8d8045…

MALICIOUS

PDF

80.7 KB Created: 2021-09-15 21:04:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 11118e4f3f699da433fb7b4c655f97a4 SHA-1: 0bb837f33e6483243cccec00a0509d1694f3061a SHA-256: a3a00990ba8d804536d1ee1acbc615e33b7a4f949a4191f5f70bcfb54ae3a7a1
154 Risk Score

Malware Insights

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

The PDF contains embedded JavaScript and multiple external URIs, indicating a malicious intent to redirect users to potentially harmful websites. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' strongly suggests this PDF is part of a phishing or malware distribution scheme. The ML classifier and ClamAV detection further confirm its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • Clickable URI points to raw IP address medium PDF_URI_IP_LITERAL
    PDF contains a clickable HTTP(S) action whose host is a literal IPv4 address. Legitimate documents normally link to named domains; raw-IP destinations are common in disposable phishing and malware-delivery infrastructure.
  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://smidgel.ru/uplcv?utm_term=gc+memory+overhead+exceeded PDF link annotation
    • http://e5tbr.alruaa.com/ckeditor-ckfinder-integration/uploads/files/83827716577.pdfIn PDF document text
    • https://mongolia-volkslift.com/uploads/files/xidawasujobuti.pdfIn PDF document text
    • http://studiopol.it/userfiles/files/mizitimumin.pdfIn PDF document text
    • https://supermagnum-bg.com/ckfinder/userfiles/files/nepiladirigiva.pdfIn PDF document text
    • https://akdenizokullari.k12.tr/wp-content/plugins/super-forms/uploads/php/files/q8liulcravd44v0v7k5dgu63b9/tinozizajivipoxuwawu.pdfIn PDF document text
    • http://bamila.vn/luutru/files/piwubimafizexekesutifamij.pdfIn PDF document text
    • http://thedewakohchang.com/image/upload/File/4844038632.pdfIn PDF document text
    • http://erpos.sk/data/files/vamuralubivemojudide.pdfIn PDF document text
    • http://chia4kids.ru/ckfinder/userfiles/files/motexu.pdfIn PDF document text
    • http://cofetariafraguta.ro/UserFiles/file/bezawikej.pdfIn PDF document text
    • http://businessplan-capalpha.fr/mbp/upload/images/images/upload/ckfinder/pusudovuv.pdfIn PDF document text
    • http://recuva.kr/upload/fck_img/1630766280/file/zojaxud.pdfIn PDF document text
    • http://185.33.116.145/~acus01/upload/files/47078193820.pdfPDF link annotation
    • https://vleek.com/uploads/files/29875064197.pdfIn PDF document text
    • https://defi128.com/userfiles/files/32646624871.pdfIn PDF document text
    • http://jfe.hk/userfiles/mudafaxurivabizijovawev.pdfIn PDF document text
    • https://mariapolis.es/ckfinder/userfiles/files/46744556868.pdfIn PDF document text
    • http://deurwater.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613e4a4ab10c9---jufofubegakugowurolamigix.pdfIn PDF document text
    • https://costabravas.com/uploads/localidades/files/befudatubuwerekasalo.pdfIn PDF document text
    • http://solyaris.pro/admin/ckfinder/userfiles/files/vilinejemerumiligovexe.pdfIn PDF document text
    • http://www.evisiontiendaonline.com/ckfinder/userfiles/files/lilepegasuloxovibisafeb.pdfIn PDF document text
    • http://www.rpv-drachten.nl/files/file/55942911472.pdfIn PDF document text
    • https://pu-sk.com/app/templates/js/ckfinder/userfiles/files/wadenarotabewubi.pdfIn PDF document text
    • http://nelly-design.ru/upload/files/jilulekemuxetoxizogurotim.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_off0000d709.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD709 17728 bytes
SHA-256: 7d41882870f60ac9df1157ee9517d46e442eb807ad97f66f8e6fb902f78bd9f8
font_01_sfnt_off00010556.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10556 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011d6d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11D6D 10448 bytes
SHA-256: 47bec7792f7794b1478a5d104f9ef331ecbbbaed44fed867e7009cbc32de337b