Malicious PDF — malware analysis report

Static analysis result for SHA-256 c9f07e714e845875…

MALICIOUS

PDF

80.8 KB Created: 2021-09-23 18:58:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 18f85a66e048835c8e9ea8232aea92fd SHA-1: 9b96d25a2a99b0453dc45ce7d518b2c5cb730d49 SHA-256: c9f07e714e8458756e15b9c6f5d534b0a3fac3de329e1afd4a1c43e09dddce7f
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external URIs, many of which point to disposable hosting and are part of a link farm. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or distributing unwanted software. The presence of embedded JavaScript suggests an attempt to execute malicious code within the PDF viewer.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

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 https://thokhoavietnam.com/upload/files/19348104750.pdf In PDF document text
    • http://euskararenginkana.eus/files/galeria/files/tilomagovefopixamin.pdfIn PDF document text
    • http://microsolder.hu/userfiles/files/78177988733.pdfIn PDF document text
    • http://furniture83.com/upload/files/bipaselefefipuvupupara.pdfIn PDF document text
    • http://gajagotour.com/UserFiles/file/sogugalawu.pdfIn PDF document text
    • http://php-lounge.de/userfiles/file/gorudixix.pdfIn PDF document text
    • http://www.gdchgs.com/admin/img/files/tikativojeziv.pdfIn PDF document text
    • https://xuantruongtech.com/images/ckeditor/files/xobesagedemogadalo.pdfIn PDF document text
    • https://tongdaidoanhnghiep.com/app/webroot/upload/files/zerovi.pdfIn PDF document text
    • http://teen.plovdivweek.com/js/ckfinder/userfiles/files/13519479923.pdfIn PDF document text
    • https://eric-parnes.com/ckfinder/userfiles/files/zikumi.pdfIn PDF document text
    • http://dyccpharma.com/upload/files/76055195738.pdfIn PDF document text
    • http://liceoadultos.juniorcollege.cl/userfiles/files/pexovaposobiterog.pdfIn PDF document text
    • http://budapesticukraszdak.hu/userfiles/files/20299114987.pdfIn PDF document text
    • http://veterinariacomportamentale.it/userfiles/files/tudobevifenu.pdfIn PDF document text
    • https://kit-veron.my/ckfinder/userfiles/files/dividupetinuwidagitosud.pdfIn PDF document text
    • https://toskov-yordanov.com/userfiles/file/18970841202.pdfIn PDF document text
    • http://2sisaccount.com/userfiles/files/rasozafetiv.pdfIn PDF document text
    • https://encouragingmath.com/wp-content/plugins/super-forms/uploads/php/files/be3279d7a93c8577dd846050090bf0e0/xekokomuw.pdfIn PDF document text
    • http://antifftech.com/uploadfile/file///2021091601014097.pdfIn PDF document text
    • http://belloverde.net/emailer/file/88382793711.pdfIn PDF document text
    • http://www.yoko-ono.be/images/userfiles/file/31327893124.pdfIn PDF document text
    • http://druckmaschinenservice.com/uploads/fce/files/38105400832.pdfIn PDF document text
    • http://pravkniga.ru/files/userfiles/files/gokexurejiralalemiwiz.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/6naE_Nh8_CY/uplcv?utm_term=download+sleep+cycle+premium+apkPDF 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_off0000d45c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD45C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ec73.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC73 10968 bytes
SHA-256: 150a3da75ff801c2cba280d02f13816db554d3018d16519004170fb17d4433f4
font_02_sfnt_off000105e8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x105E8 18708 bytes
SHA-256: d51185c1a8d0221c39591875965130171bcfcfb6888ed9c6b6f932ba84b23a28