Malicious PDF — malware analysis report

Static analysis result for SHA-256 a9631ae7170bc553…

MALICIOUS

PDF

82.6 KB Created: 2021-09-22 23:35:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 01c999b2cb689b25b0ed5d6a24c0d640 SHA-1: a1cb51552acebc7cb8acf93b9abae4d9554ebc7e SHA-256: a9631ae7170bc55351699c0457a6bf738c937c9cad8cf959de98930c71346b5c
142 Risk Score

Malware Insights

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

This PDF file was flagged by multiple heuristics, including a critical ClamAV detection for 'Pdf.Phishing.Trojan'. The presence of embedded JavaScript and numerous external links, some hosted on disposable domains, suggests an attempt to deliver a malicious payload or redirect users to a phishing site. The ML classifier also strongly indicated maliciousness.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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
  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://philabc.ru/uplcv?utm_term=nds+apk+full PDF link annotation
    • https://rts-wm.com/ckfinder/userfiles/files/77210499690.pdfIn PDF document text
    • http://inbeeldt.nl/userfiles/file/29374396546.pdfIn PDF document text
    • http://officeharbor.com/pdtInfo/35783350367.pdfIn PDF document text
    • http://daglichtfilters.nl/ckfinder/userfiles/files/22188715923.pdfIn PDF document text
    • https://ijieet.org/ckfinder/userfiles/files/kupad.pdfIn PDF document text
    • https://ariconium.cz/webpagebuilder/ckfinder/userfiles/files/90451283007.pdfIn PDF document text
    • http://molenat-energies.fr/molenat.com/images/editor/file/19007011742.pdfIn PDF document text
    • http://sk-uralstroy.ru/uploads/files/lefuw.pdfIn PDF document text
    • http://www.greddy.com/admin/common/ckfinder/userfiles/File/63692057356.pdfIn PDF document text
    • http://clingac.com/d/files/voleguzuwixerefulikabap.pdfIn PDF document text
    • https://www.officinadelgustoroma.com/wp-content/plugins/super-forms/uploads/php/files/f000e01519a8c8be44cbdcc69ef80264/sumuwelexaxutunogaruwolif.pdfIn PDF document text
    • http://dok-vo.ru/userfiles/file/24563237577.pdfIn PDF document text
    • https://rizecanreklam.com/images/file/30682825872.pdfIn PDF document text
    • http://yachts-trade.com/files/3138841814.pdfIn PDF document text
    • http://www.cavice.fi/tiedostot/files/femolopo.pdfIn PDF document text
    • http://warwick-ems.org/userfiles/file/62902385909.pdfIn PDF document text
    • http://hoangduy.vn/vn/files/nirozutumofewuk.pdfIn PDF document text
    • http://husplaza.hu/editor_up/vorijagijadalani.pdfIn PDF document text
    • http://studiotecnicodavico.eu/userfiles/files/29083760979.pdfIn PDF document text
    • https://33mobility.net/uploads/files/woravak.pdfIn PDF document text
    • http://geyikkimya.com/userfiles/upload/file/futelupogolinupuv.pdfIn PDF document text
    • https://agros.net/uploads/file/92130372457.pdfIn PDF document text
    • http://arcstema.com/userfiles/files/82458044635.pdfIn PDF document text
    • http://iwilldoit.ru/uploads/files/files/gugoxabolitalev.pdfIn PDF document text
    • https://i-chat.tw/js/ckfinder/userfiles/files/15865485491.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_off0000dcb2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDCB2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f4c4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF4C4 19144 bytes
SHA-256: 08fbca651785599bf103e33f79d411b66f29ca21a1e62f7baa7ae7be3e172afa
font_02_sfnt_off00012659.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12659 10012 bytes
SHA-256: ebe49a21ac687db61536b28f5d117f91001aa662bbf1267d0ebff2f3ab8d2f61