Malicious PDF — malware analysis report

Static analysis result for SHA-256 3c3c4a2b36735b51…

MALICIOUS

PDF

83.6 KB Created: 2021-09-08 18:52:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 2774d2175ccdb560eb189ac1fdfff901 SHA-1: 36256bea7bdc7f899bd6db9af01fc1c7615fd35e SHA-256: 3c3c4a2b36735b512cf8bcc575d5b7731b1cb5cdb230edb2c2d0a2069b88586f
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF file detected by ClamAV as a phishing trojan. It contains embedded JavaScript and numerous external URIs, many of which point to disposable domains and appear to be part of a link farm. The ML classifier also flagged this PDF with high confidence. The embedded JavaScript likely facilitates the redirection to malicious sites, contributing to the overall phishing or malware distribution goal.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9911

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://kommunikator.nu/demo/userfiles/file///99826560762.pdf In PDF document text
    • http://ave-france.com/pics/files/92152089202.pdfIn PDF document text
    • http://visusmarble.com/images_upload/files/1951716213.pdfIn PDF document text
    • http://yhbinternational.com/userfiles/file/zovojizusaredatalevazero.pdfIn PDF document text
    • https://kvizek.hu/ckfinder/userfiles/files/lezisawuzo.pdfIn PDF document text
    • http://abwhopewell.com/uploads/files/wesimeberuxedusegemaja.pdfIn PDF document text
    • https://www.puskinas.lt/ckfinder/userfiles/files/39519632069.pdfIn PDF document text
    • http://palaciodelosnavas.com/userfiles/file/68352444712.pdfIn PDF document text
    • http://pantryscan.com/123cars/imagefck/file/85267068139.pdfIn PDF document text
    • http://fabriquetextil.com/js/new/fckeditor/userfiles/file/bupelele.pdfIn PDF document text
    • http://centralgiving.com/media/userfiles/file/zatewi.pdfIn PDF document text
    • http://boston.pl/fck_pliki/file/4954073294.pdfIn PDF document text
    • https://kheops-so.fr/ckfinder/userfiles/files/8564248892.pdfIn PDF document text
    • http://zoltysnieg.pl/pliki_wyswig/files/jikekuvegorevononorul.pdfIn PDF document text
    • http://www.jimenez-casquet.com/wp-content/plugins/formcraft/file-upload/server/content/files/16134fcc95d617---kotuveromikiza.pdfIn PDF document text
    • https://corumosmanlimakina.com/js/ckfinder/userfiles/files/36215362449.pdfIn PDF document text
    • http://sochi-polyana.com/ckfinder/userfiles/files/43901706902.pdfIn PDF document text
    • https://ans5680.preneed91.com/upload/files/49098292227.pdfIn PDF document text
    • http://proreferee.ru/uploads/ckfinder/files/94310250489.pdfIn PDF document text
    • https://gamedunyasi.com/calisma2/files/uploads/keremufadisujos.pdfIn PDF document text
    • https://infiniteprospects.com/FCKeditor/file/28242055698.pdfIn PDF document text
    • http://steelbo.com/uploads/admins/u0/files/20210908233007.pdfIn PDF document text
    • http://855solution.com/htdocs/cljr/data/files/52823744266.pdfIn PDF document text
    • http://dubilex.com/userfiles/files/37901970284.pdfIn PDF document text
    • https://www.willmarshelter.com/ckfinder/userfiles/files/66560730239.pdfIn PDF document text
    • http://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/16134682e2f998---71919811870.pdfIn PDF document text
    • http://garankuccu.com/upload/fckimagesfile/517320f343fc75daa1f3091ab4863611.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/A3Ryygt5BCM/uplcv?utm_term=general+supplies+company+profile+in+kenya+pdfPDF 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_off0000de20.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE20 18712 bytes
SHA-256: e6b5c6b6ab31a13c91894683a2689070d587fafb62581cfd4f7cd23e8fe4c884
font_01_sfnt_off00010e6e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10E6E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012685.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12685 11028 bytes
SHA-256: 9229a86c7b1aa0060d96e1fcf16052df48c3dfaaab712d4256ad52814cf69215