Malicious PDF — malware analysis report

Static analysis result for SHA-256 91213309ca5f714a…

MALICIOUS

PDF

71.8 KB Created: 2021-09-28 02:02:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 9fbd8411e9d777636b419ce102c5abf8 SHA-1: ac55855c52919242cef86273d52bf56d821c94bc SHA-256: 91213309ca5f714ab6d850c012428200755e1800104d43cb68d0b0afbdbd5d4c
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and a high number of external URIs, many of which are hosted on domains with low reputation or are part of a link farm. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to redirect users to malicious sites for further exploitation or phishing. The embedded JavaScript is a common technique for initiating malicious actions within PDFs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 6

  • 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.
  • 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 http://sattosushi.com/uploads/files/40420132289.pdf In PDF document text
    • https://srmhomes.com/images/bulk_images/files/3734492118.pdfIn PDF document text
    • https://perfecthospital.org/FCKeditor/file/zunupola.pdfIn PDF document text
    • https://produktybhp.pl/pliki_user/File/75164008393.pdfIn PDF document text
    • https://fertilizerproductionprocess.com/d/files/gufulonewoxegudizo.pdfIn PDF document text
    • https://bandotrading.com/uploads/file/65501008486.pdfIn PDF document text
    • http://elateridae.com/images/FCKeditor/file/butikegudididozomavod.pdfIn PDF document text
    • https://autoradiator.mn/uploads/ckfinder/files/likovozalu.pdfIn PDF document text
    • http://www.park-seversk.ru/other/js/ckfinder/userfiles/files/wilujimuwi.pdfIn PDF document text
    • https://semineebrasov.ro/printuri-fi/files/busesabixuloj.pdfIn PDF document text
    • http://hoangnamjsc.com/upload/files/2464129716.pdfIn PDF document text
    • http://umffz21.ru/admin/ckfinder/userfiles/files/5216765373.pdfIn PDF document text
    • https://funstore.dialog.org/userfiles/file/lonarekojevuvelexuf.pdfIn PDF document text
    • http://yugreat.com/filespath/files/20210901112547.pdfIn PDF document text
    • http://palestraarkadia.it/userfiles/files/78987952156.pdfIn PDF document text
    • http://reiki-roots.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1612ec07c9d68a---zupakasujo.pdfIn PDF document text
    • https://consultemergingmarkets.cubsindia.com/files/66107985767.pdfIn PDF document text
    • http://mylodge-naoshima.com/6423251741.pdfIn PDF document text
    • http://homeloanz.net/images/e/file/44840122849.pdfIn PDF document text
    • http://photopuzzle.net/userData/board/file/vazupiguxamajesa.pdfIn PDF document text
    • https://igescanada.com/ckfinder/userfiles/files/44136718909.pdfIn PDF document text
    • http://fivelscope.net/fckimages/36319920977.pdfIn PDF document text
    • http://www.jysunshine-hotel.com/up_files/file/15507782834.pdfIn PDF document text
    • http://weilandvloeren.nl/fckimages/77375757092.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3CAf4wW3hvY/uplcv?utm_term=play+simcity+2000+online+freePDF 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_off0000b280.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB280 17040 bytes
SHA-256: 2173a34c8af930559f2efa553f9db94ba4073df63dda0d6cc1074a0e2aa1e683
font_01_sfnt_off0000debc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDEBC 10856 bytes
SHA-256: 19604e145d25be08dbe13885917fcb61500c651d0eb4b4f7ead2c2db78ec4eb5
font_02_sfnt_off0000f7e7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF7E7 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1