Malicious PDF — malware analysis report

Static analysis result for SHA-256 39a47b5cec4d0eb2…

MALICIOUS

PDF

79.4 KB Created: 2021-09-16 07:47:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 402707e93b9e958ea8a521f421e2c0f1 SHA-1: 71ca466b7e710f7e090a87b3fcd78dda2628c01a SHA-256: 39a47b5cec4d0eb21ccb19a0465bb935ba70fdc53390bfbf828b484189688dc9
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF document contains numerous embedded URLs pointing to various domains, many of which are structured to host PDF files. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a high likelihood of this document being part of a link farm designed to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly support its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 5

  • 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.
  • 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://umiyawoodworks.com/fckdb/userfiles/file/gezadapoxodajibum.pdf In PDF document text
    • http://langeline.com/ckeditor/upload/files/68423324152.pdfIn PDF document text
    • http://skisun.it/userfiles/files/86127327584.pdfIn PDF document text
    • http://studiogeologicotrilobite.com/userfiles/files/59173500382.pdfIn PDF document text
    • http://www.39koratmachinery.com/file_upload/files/47210090402.pdfIn PDF document text
    • http://www.infranetltd.com/wp-content/plugins/formcraft/file-upload/server/content/files/16136895adde7e---fivob.pdfIn PDF document text
    • https://riminabda.sk/userfiles/file/10313494980.pdfIn PDF document text
    • http://nfraccon.org/userfiles/file/wazesuvekazekajux.pdfIn PDF document text
    • https://marbeyoyun.com/calisma2/files/uploads/72684941551.pdfIn PDF document text
    • http://technology-mp.it/userfiles/files/zuvikumuvosodi.pdfIn PDF document text
    • http://vanillasky-ch.com/images/files/72613210337.pdfIn PDF document text
    • http://hanboo.cn/Uploads/file/2021091401220770554.pdfIn PDF document text
    • http://elementyzlaczne.pl/media/file/rufupinosig.pdfIn PDF document text
    • http://residenzaeden-albisola.com/userfiles/files/38881018811.pdfIn PDF document text
    • http://archiwum.wyryki.eu/admin/ckfinder/userfiles/files/99588369110.pdfIn PDF document text
    • http://palaciodelosnavas.com/userfiles/file/9882034549.pdfIn PDF document text
    • http://pescepiana.eu/userfiles/files/45984048648.pdfIn PDF document text
    • http://okna-dvere-online.cz/media/upload/upload/file/85377806895.pdfIn PDF document text
    • http://ttfi.org/app/webroot/userfiles/file/46173427602.pdfIn PDF document text
    • https://unique-u.biz/images/uploads/file/96801081478.pdfIn PDF document text
    • https://eprobatdz.com/ckfinder/userfiles/files/25360471891.pdfIn PDF document text
    • https://thieumaunao.vn/workspace/develop/uploads/ck_upload/files/31051590045.pdfIn PDF document text
    • https://leise.ru/admin/ckfinder/userfiles/files/losikomoxirule.pdfIn PDF document text
    • https://inprovitcolombia.com/ckfinder/userfiles/files/45456859657.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BkSY9tpko7c/uplcv?utm_term=how+do+you+transfer+from+an+android+to+an+iphonePDF 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_off0000d04b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD04B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e85d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE85D 17680 bytes
SHA-256: fa49d4905bfb924f3ff9c9492bbfb93de631da75458b5784bf2087c356815d22
font_02_sfnt_off000115ea.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x115EA 11008 bytes
SHA-256: 98025f30c85066e15df262cae990d4188c35cd0ff2126bd1d23b5efff1266578