Malicious PDF — malware analysis report

Static analysis result for SHA-256 4e28bc5904ed1f9c…

MALICIOUS

PDF

82.1 KB Created: 2021-10-06 00:48:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: ce4900abcfd6b74910746c70042e9584 SHA-1: 19a6557a008292ef5b96edb1b5ef947f9175a212 SHA-256: 4e28bc5904ed1f9c0ba3982592e1d273adcd009246cc8ec77f035f0db511f7a8
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as a malicious PDF by ClamAV and an ML classifier. It contains embedded JavaScript and numerous external URIs, many of which point to PDF files hosted on potentially disposable domains, suggesting a link farm or phishing lure. The presence of embedded JavaScript indicates an attempt to execute code within the PDF viewer.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://sanraimundo.cl/dyn/uploads/file/disudadalikumudogitik.pdf In PDF document text
    • http://ntouioc.ntou.edu.tw/ckfinder/userfiles/files/voderusepuketuxijojumumak.pdfIn PDF document text
    • https://manenshop.com/upload/files/91484257492.pdfIn PDF document text
    • http://aromamahabaleshwar.com/ckfinder/userfiles/files/30572396726.pdfIn PDF document text
    • http://cokhilegia.com/upload/files/zekuxeganotuz.pdfIn PDF document text
    • http://host.keraladreamhomes.com/~viswabrahmathach/admin/fckeditor/editor/filemanager/connectors/php/userfiles/file/zexizejififefojudorijub.pdfIn PDF document text
    • http://www.chatanakonci.cz/userfiles/file/zusuj.pdfIn PDF document text
    • http://csc0535.com/userfiles/file/20210924043228_jpxdac.pdfIn PDF document text
    • http://bonezi.morefriendship.com/upload/files/33242345518.pdfIn PDF document text
    • https://pecsikult.hu/files/file/jewurolewotujokusoboremo.pdfIn PDF document text
    • https://designclarf.it/file/potafozanasujabuzixuze.pdfIn PDF document text
    • https://stallion-international.com/userfiles/file/26148292275.pdfIn PDF document text
    • https://veritiesinstitute.com/wp-content/plugins/super-forms/uploads/php/files/998d147372bb8eb13b975c2c5b6a3900/75260356445.pdfIn PDF document text
    • https://manhremhoangvan.vn/wp-content/uploads/files/fodima.pdfIn PDF document text
    • http://pieseclimaauto.com/files/file/jaloj.pdfIn PDF document text
    • http://e-skala.pl/userfiles/file/luzagafijoratigudaki.pdfIn PDF document text
    • http://sksound.com/userfiles/file/68385823463.pdfIn PDF document text
    • http://abwingsmd.com/uploads/files/12418823117.pdfIn PDF document text
    • http://nontaromclinic.com/ckfinder/userfiles/files/437972973.pdfIn PDF document text
    • http://fratellilongoni.com/userfiles/files/noxofizojovajugipevoror.pdfIn PDF document text
    • http://oppedisanorobertosrl.com/userfiles/files/gisolevezifavogurutufokif.pdfIn PDF document text
    • https://dm288.rs/slicice/file/vojoresug.pdfIn PDF document text
    • http://worldplastsolution.com/ckfinder/userfiles/files/59686673183.pdfIn PDF document text
    • https://www.agro-zavod.ru/app/webroot/js/ckfinder/userfiles/files/70051144827.pdfIn PDF document text
    • http://elvirajogsi.hu/ckfinder/userfiles/files/tutipiwusumuru.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/YTWXjIUwRh0/uplcv?utm_term=cream+of+spinach+soupPDF 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_off0000d925.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD925 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f137.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF137 18908 bytes
SHA-256: d9f0abc22d5472ab50997a3bfd88b62b8c86c8ed6b07521c5f11d4e736bc54fd
font_02_sfnt_off0001225f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1225F 10732 bytes
SHA-256: 18a34b7fed514d3598c307ab13cbfb2fb641ca6664ebb07603d9116e14ef5ec7