Malicious PDF — malware analysis report

Static analysis result for SHA-256 ebf96abc739b0e70…

MALICIOUS

PDF

70.2 KB Created: 2021-10-09 04:52:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 4c1a714e81000837e36609466d28b0a9 SHA-1: af0595b4eded96c97fff75ef891f732617bf4030 SHA-256: ebf96abc739b0e70cd95829e6db56128f93b3bfb0b9133fdce76e4c5633ae33e
66 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The ML classifier strongly indicated maliciousness, and the PDF contains numerous embedded URLs pointing to a link farm. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' confirms the nature of these links, suggesting a campaign to distribute further malicious content or phish users. No scripts were extracted, limiting the analysis of direct execution vectors.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9986

Heuristics 4

  • 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 http://lnyuanzong.com/uploads/files/20210902202630.pdf In PDF document text
    • https://zbmbudomont.pl/userfiles/file/81935364469.pdfIn PDF document text
    • http://ngocphuocjsc.com/public/default/ckeditor/files/66169709652.pdfIn PDF document text
    • https://angkalaris.com/contents/files/85946694023.pdfIn PDF document text
    • https://toolsatool.com/userfiles/files/53220508345.pdfIn PDF document text
    • http://mashhadgardi724.ir/basefile/mashhadgardi724/files/komuvurigawuzugififaxek.pdfIn PDF document text
    • http://brandnewgoods.net/userfiles/file/58973328715.pdfIn PDF document text
    • http://hotelborgodeipoeti.com/userfiles/files/46523554704.pdfIn PDF document text
    • http://wasserentkalkung.at/ckfinder/userfiles/files/88084377881.pdfIn PDF document text
    • http://archi-m.ru/userfiles/file/64128775777.pdfIn PDF document text
    • http://capmar.eu/userfiles/file/13111060704.pdfIn PDF document text
    • https://steklo-shik.ru/userfiles/file/suzolizodazubowigot.pdfIn PDF document text
    • http://xn--80affcyoc0ac1f6a.xn--p1ai/admin/modules/ckeditor/ckfinder/userfiles/files/wiwawuvogi.pdfIn PDF document text
    • https://coastalholidayproperty.com/ckfinder/userfiles/files/47475901670.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614b76ee163a2---12721325379.pdfIn PDF document text
    • http://att-na.com/upload/getob.pdfIn PDF document text
    • http://wo-kop.pl/userfiles/file/57745933390.pdfIn PDF document text
    • http://slowjamsundays.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614234b4c1651---texibopeselavix.pdfIn PDF document text
    • http://stark-tools.ru/images/uploaded/15683278502.pdfIn PDF document text
    • https://www.sonorisation-auxerre.fr/ckfinder/userfiles/files/defitebad.pdfIn PDF document text
    • https://gs-hemeringen.de/ablage/userfiles/files/67105475078.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1xuhb7AK25c/uplcv?utm_term=oracle+java+code+conventions+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_off0000b3dd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB3DD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000cbef.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCBEF 15228 bytes
SHA-256: f038a5c3ea1502a40edcd1de1a58635c43f3e48aea5af2f961e7dcccd697185b
font_02_sfnt_off0000f24d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF24D 10836 bytes
SHA-256: d1e7b2d066e405b9ecc54c6bcaaa0e9389629cb38f7ecaf4364becb70bdb73f8