Malicious PDF — malware analysis report

Static analysis result for SHA-256 c9774f2c23b2c7bf…

MALICIOUS

PDF

95.7 KB Created: 2021-09-08 15:35:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: c6b8743296bf58a9087f2c85b36a80b4 SHA-1: 9b188d36c9a58c9d24ee8fa19235147f0879f868 SHA-256: c9774f2c23b2c7bf0f8742f5f019e38b75229de728fc0c2cecc8016728a2584a
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains embedded JavaScript, which is a common technique for executing malicious code within PDFs. The numerous external URLs, many pointing to PDF files, suggest a link farm or redirection mechanism designed to lead users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

Heuristics 6

  • 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.
  • 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://audiomaster.se/wp-content/plugins/formcraft/file-upload/server/content/files/16137631575c76---kofabebalitapudufiruvopi.pdf In PDF document text
    • http://abw10thstreetne.com/uploads/files/87214226052.pdfIn PDF document text
    • https://iqmuseum.mn/uploads/files/kazirefudanasanes.pdfIn PDF document text
    • http://alt-1c.ru/userfiles/file/xigari.pdfIn PDF document text
    • http://rklatex.com/userfiles/file/tofusinasukegesololiw.pdfIn PDF document text
    • http://arcos-eff.it/userfiles/files/4763233272.pdfIn PDF document text
    • http://ogledalata.bg/uploads/pages/files/tifado.pdfIn PDF document text
    • http://countryclaim.cz/userfiles/file/4881076234.pdfIn PDF document text
    • http://newmob.it/userfiles/files/suwabigorileribodusaji.pdfIn PDF document text
    • http://parentini.it/userfiles/files/xudakekumeluwaleno.pdfIn PDF document text
    • https://mosconi.net/userfiles/file/simodoxil.pdfIn PDF document text
    • http://cgpreceptor.com/ckfinder/userfiles/files/85878916249.pdfIn PDF document text
    • http://udelimpa.es/ckfinder/userfiles/files/zatejivumutukazurumesija.pdfIn PDF document text
    • http://www.sunarmisir.com.tr/wp-content/plugins/super-forms/uploads/php/files/99mi5tifuauc21a5o2d8cp9i24/zedapenewalefumekizasor.pdfIn PDF document text
    • https://mklaassen.nl/images/file/88536287320.pdfIn PDF document text
    • https://solelane.com/ckfinder/userfiles/files/mavubinazelibijotitumed.pdfIn PDF document text
    • https://reclamesticker.nl/images/uploads/file/In PDF document text
    • http://bscartridge.com/pic/28523022304.pdfIn PDF document text
    • https://zagi.hr/files/nidugovumobadu.pdfIn PDF document text
    • http://lohoithaiduong.com/uploads/files/pebovesukufufewovoko.pdfIn PDF document text
    • https://luxesystem.site/js/ckfinder/userfiles/files/bopigovarejepisijikasabik.pdfIn PDF document text
    • https://ukmalayalamnews.com/userfiles/file/terazamoxuduredefeguzir.pdfIn PDF document text
    • https://cafesca.mx/ckfinder/userfiles/files/defalebipojikoxepele.pdfIn PDF document text
    • https://llbyggodesign.se/UserFiles/files/bomuwujirobimidafevukema.pdfIn PDF document text
    • https://dolphinsolutions.net/ckfinder/userfiles/files/49593101825.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/6naE_Nh8_CY/uplcv?utm_term=total+knee+replacement+rehabilitation+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_off000111c0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x111C0 17788 bytes
SHA-256: 29387601fa18943a9a507f5532c836aa245154099010083d36719a88b942d6c1
font_01_sfnt_off00013ffe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13FFE 10912 bytes
SHA-256: 448b4aa715614d7cb21d4e8f79081add2fa201b0c12f5e74935b38f4de2ca666
font_02_sfnt_off000158cb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x158CB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1