Malicious PDF — malware analysis report

Static analysis result for SHA-256 ad81b6e9a840ce39…

MALICIOUS

PDF

75.9 KB Created: 2021-09-16 11:54:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: c5f19688669de3d8a0a12b732f740cd2 SHA-1: 2f998c746957b0ab71e2213bf1ee6dd174eca369 SHA-256: ad81b6e9a840ce3938efc8fc6dbf50c5a4594035ce7e5176088a24224c47e0a4
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is identified as malicious by ClamAV and an ML classifier, with heuristics indicating embedded JavaScript and external URIs. The PDF acts as a link farm, directing users to numerous disposable domains, a common tactic for phishing or distributing further malware. The presence of embedded JavaScript suggests an attempt to exploit PDF vulnerabilities or execute malicious code.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

Heuristics 6

  • 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.
  • 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://infrive.ru/uplcv?utm_term=print+awareness+checklist PDF link annotation
    • https://iwanbim.com/userfiles/files/9564476990.pdfIn PDF document text
    • http://cck-brno.cz/ckfinder/userfiles/files/lajupusevizitesafaxale.pdfIn PDF document text
    • http://queensparkview.com/image/upload/File/zoniduwogexex.pdfIn PDF document text
    • http://newbusan.net/FileData/ckfinder/files/20210916_A930C23625BC092E.pdfIn PDF document text
    • http://duetsepolno.pl/userfiles/file/bubipudo.pdfIn PDF document text
    • https://banerjeetourspecial.in/ckfinder/userfiles/files/80116551751.pdfIn PDF document text
    • http://temple.mo/userfiles/file/gosevakovefi.pdfIn PDF document text
    • http://xn--nellieskche-0hb.de/userfiles/file/77160497370.pdfIn PDF document text
    • http://vidol.nl/userfiles/file/kumogigakid.pdfIn PDF document text
    • https://dijitalsanat.link/upload/files/bafeji.pdfIn PDF document text
    • http://robalton.es/Albums/images/file///97543899156.pdfIn PDF document text
    • https://eastmangroup.org/ckfinder/userfiles/files/nibabuladarojafan.pdfIn PDF document text
    • https://dbhattacharjee.com/ckfinder/userfiles/files/45310059292.pdfIn PDF document text
    • http://homeloanz.net/images/e/file/sofuzepaduzugogumuvige.pdfIn PDF document text
    • http://robotsuk.com/luckingbros.co.uk/userfiles/files/59238019505.pdfIn PDF document text
    • http://www.prunay-en-yvelines.fr/ckfinder/userfiles/files/79779625369.pdfIn PDF document text
    • http://fuguchair.com/upfolder/e/files/20210910140727.pdfIn PDF document text
    • https://casasholidays.com/scgtest/team-explore/uploads/files/37735351646.pdfIn PDF document text
    • https://khanoomhoteli.com/basefile/khanoomhotelicom/files/59604625905.pdfIn PDF document text
    • http://le-lemniscus-incandescent.fr/ckeditor/upload/files/vofex.pdfIn PDF document text
    • http://careerhack.net/wp-content/plugins/formcraft/file-upload/server/content/files/1613ab8e542e87---74519434439.pdfIn PDF document text
    • http://club-integra.ru/userfiles/file/gowitarulodifujak.pdfIn PDF document text
    • https://keiba-like.biz/js/ckfinder/userfiles/files/jopakatirezuxitazod.pdfIn PDF document text
    • http://totalfinance.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1613f69cae967e---76220138777.pdfIn PDF document text
    • 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_off0000c41a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC41A 18084 bytes
SHA-256: 4455b9983a8266f9cabc5e2307cb895dcb51aaa857f61509929ab278543c04ed
font_01_sfnt_off0000f2ca.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF2CA 10384 bytes
SHA-256: 29ee2beafd86bfef9adfbf75b44d17f0eb61b2b387e00bba071ae4fd2be5639b
font_02_sfnt_off00010a44.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A44 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1