Malicious PDF — malware analysis report

Static analysis result for SHA-256 a1634f20f2a9fd63…

MALICIOUS

PDF

84.0 KB Created: 2021-09-18 18:02:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 7a638a8a022754ecb3f1db288d92544a SHA-1: ff748d0c0aa42f7d591d884417cdf57b44328cd9 SHA-256: a1634f20f2a9fd632e4f792c9c327e90b3985366bd0e785190b5c8bdd1a8d2ec
74 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript, a common technique for executing malicious code within documents. It also includes numerous external URIs, many of which are hosted on potentially disposable domains, suggesting a link farm or phishing attempt. The ML classifier strongly indicates malicious intent, and the presence of JavaScript points to an attempt to download and execute further payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9860

Heuristics 5

  • 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 https://tyko.pl/userfiles/file/zabodafazusame.pdf In PDF document text
    • https://isigakizima.net/img/tmp/file/60032365421.pdfIn PDF document text
    • http://www.enfersalus.com/ckfinder/userfiles/files/faxosotek.pdfIn PDF document text
    • https://xn--49st2et51duvk.com/upload/files/fakibisopagofowuxujom.pdfIn PDF document text
    • http://teen.plovdivweek.com/js/ckfinder/userfiles/files/88976474375.pdfIn PDF document text
    • http://nesemlak.com/test/images/uploads/files/sijuwosobulugokopurer.pdfIn PDF document text
    • https://sysyanginguvenlik.com/uploads/files/ribaduwepasuvujado.pdfIn PDF document text
    • https://www.urban-quartz.co.uk/wp-content/plugins/super-forms/uploads/php/files/08ace139f336d33e0688566e008db14a/gupomevuzelenejawidarapa.pdfIn PDF document text
    • https://x-leather.com/radsportfiles/file/selukaxifiner.pdfIn PDF document text
    • http://crabandclaw.com/uploads/files/fidoxovikijusan.pdfIn PDF document text
    • http://alfadent-volg.ru/images_uploads/files/pupixel.pdfIn PDF document text
    • http://buzmakov-ua.ru/admin/ckfinder/userfiles/files/wumewuxono.pdfIn PDF document text
    • http://crosswaysrecruitment.com/userfiles/file/17539080371.pdfIn PDF document text
    • https://hr-serdahel.hu/images/file/xavozenezitifuxupoxopepof.pdfIn PDF document text
    • http://csc-021.com/userfiles/file/20210903161710_2z0tjr.pdfIn PDF document text
    • http://vasekurzy.cz/userfiles/file/donirikabupivowuwoniku.pdfIn PDF document text
    • http://pnlestari.com/visitbali/image/files/pivusevupulip.pdfIn PDF document text
    • https://www.pepinieres-gey.fr/ckfinder/userfiles/files/katenir.pdfIn PDF document text
    • http://ex2010.com/uploadfile/file/2021091407561773499.pdfIn PDF document text
    • http://saiprogetti.net/userfiles/files/64608156408.pdfIn PDF document text
    • http://0985028898.kad.tw/kads/ckfinder/userfiles/files/86951378168.pdfIn PDF document text
    • https://kirmatas.com/userfiles/file/simipafiderexadal.pdfIn PDF document text
    • http://www.performhabitat.fr/bundles/astadmin/js/ckfinder/userfiles/files/fusajukuda.pdfIn PDF document text
    • http://evaemlak.com/userfiles/file///pepewipazakefuveg.pdfIn PDF document text
    • https://hawkseyetravels.com/assets/ckfinder/userfiles/files/woxobatemefaridu.pdfIn PDF document text
    • https://datenglagi.com/contents/files/75629628978.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1KS0DP0cxss/uplcv?utm_term=i+am+app+androidPDF 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_off0000e592.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE592 10060 bytes
SHA-256: f689112c4a1445386bb47d4064501f2636300af706f52eedc27c806fa1a4219c
font_01_sfnt_off0000fbbb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFBBB 17932 bytes
SHA-256: 5a9693b455617654f67a5d7fa350c4b5780470ba2d4eabc7f71c5f79341a2c4f
font_02_sfnt_off00012a97.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12A97 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1