Malicious PDF — malware analysis report

Static analysis result for SHA-256 24f9d521f40adef5…

MALICIOUS

PDF

83.4 KB Created: 2021-09-12 15:25:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 9b942eb211208fbe07361928b63bcaed SHA-1: 81a0c49be64facf1c64446ae99999ca62db04805 SHA-256: 24f9d521f40adef5da208b50dcb630161895e7aee0bda64b249e108d602f33f2
142 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and multiple URLs, many of which are part of a link farm designed to obscure the true destination. The presence of a visual download button and the ML classifier's high confidence score indicate a malicious intent to trick the user into downloading further malware. The ClamAV detection further supports this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 7

  • 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.
  • 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 http://jkbprivateiti.com/userfiles/file/zubegoginupupivozotobezan.pdf In PDF document text
    • http://daeryuhealthcare.com/ckupload/files/6187544531.pdfIn PDF document text
    • http://dh-cell.com/ckfinder/userfiles/files/91260169464.pdfIn PDF document text
    • https://bursac.net/userfiles/file/natogimeziseseli.pdfIn PDF document text
    • http://conhantaoankhanh.com/webroot/img/files/lodijij.pdfIn PDF document text
    • https://jordan.si/dokumenti/file/6784107596.pdfIn PDF document text
    • http://aibasavar.edu.bd/app/webroot/ckfinder/userfiles/files/lapugegukofozupiwodog.pdfIn PDF document text
    • http://fujieshubao.com/zk/UploadFile/file/2021090823204673499.pdfIn PDF document text
    • http://aeon-dev.com/uploads/files/202109030214188850.pdfIn PDF document text
    • http://mtecommerce.it/public/news/file/14309037285.pdfIn PDF document text
    • http://vanhacollection.com/images/files/39266205066.pdfIn PDF document text
    • http://neodentpetrosino.it/userfiles/files/tazegixigitugufogalo.pdfIn PDF document text
    • https://extremedriveline.com/ckfinder/userfiles/files/999765280.pdfIn PDF document text
    • http://natalieshuff.com/uploads/file/46200276256.pdfIn PDF document text
    • http://khangvietdn.com/uploads/file/velamebovisoxuviwupanavo.pdfIn PDF document text
    • http://gameadvisers.com/js/new/fckeditor/userfiles/file/jemozenaxovovopa.pdfIn PDF document text
    • https://ermolino.mebel18.com/uploads/files/14658912286.pdfIn PDF document text
    • http://adamlegal.com/userfiles/file/powobez.pdfIn PDF document text
    • http://herve-coiffure.ci/files/sexota.pdfIn PDF document text
    • http://hoteldanang.com/uploads/images/files/55510473716.pdfIn PDF document text
    • https://drlalashow.com/php/billboard/uploads/file/79725980812.pdfIn PDF document text
    • https://ecoquimica.cl/dinamicos/uploads/file/nadiderovunujebijer.pdfIn PDF document text
    • http://modernplating.com/userfiles/file/80348753235.pdfIn PDF document text
    • http://digjamaica.com/app/webroot/files/jilejagikizif.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BkSY9tpko7c/uplcv?utm_term=fundamentals+of+fluid+mechanics+5th+edition+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_off0000e29f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE29F 10996 bytes
SHA-256: 330f3ab7347a2efd88255d88b828323eec3ace5c543694394d2f5db1ccbe23a8
font_01_sfnt_off0000fbfe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFBFE 16924 bytes
SHA-256: 6adfb5d347f987bb70762050f722e0c9cb3351b6ad8444cf88466c9dfc19ce9c
font_02_sfnt_off0001276a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1276A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1