Malicious PDF — malware analysis report

Static analysis result for SHA-256 a636227a6d6a46c1…

MALICIOUS

PDF

87.5 KB Created: 2021-09-12 07:57:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 5e1e38ee84c410a283cdc45b18ffdb9f SHA-1: 91118793f64211af901eaf73af5bab8503002b35 SHA-256: a636227a6d6a46c12168e7580b1a9b5f6050c97f8f4066ea54683075923fb20c
134 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 exhibits characteristics of a link farm, with numerous external URIs pointing to disposable hosting, suggesting an attempt to obscure the final destination or distribute payloads. The ClamAV detection and ML classifier further support its malicious nature, likely as a phishing lure or a downloader for further stages.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9905

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://ip-kamera-rendszer.nuttydog.hu/ckfinder/userfiles/files/wipiwuwivopaf.pdf In PDF document text
    • http://alacarte-grafik.de/userfiles/file/86632376535.pdfIn PDF document text
    • https://himarco.ir/basefile/himarcoir/files/worasabopumov.pdfIn PDF document text
    • http://salukool.ee/upload/userfiles/file/72880142858.pdfIn PDF document text
    • http://automsystem.com/UploadFile/file/20210909014910447.pdfIn PDF document text
    • http://csp.hu/editor_up/sebaso.pdfIn PDF document text
    • https://khanoomhoteli.com/basefile/khanoomhotelicom/files/4676350834.pdfIn PDF document text
    • https://mimpishio2bet.net/contents/files/duvokiv.pdfIn PDF document text
    • http://studioaba.net/userfiles/files/kodenomibofebofe.pdfIn PDF document text
    • https://at1-turbo-j3t.com/contents/files/22360238398.pdfIn PDF document text
    • http://phatnang.com/media/ftp/file/gubof.pdfIn PDF document text
    • http://schokoladenfontaene.de/idata/xitirusijiriganesup.pdfIn PDF document text
    • http://www.optionassurance.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1613c3dff48b05---54007076223.pdfIn PDF document text
    • http://plovdivweek.com/app/templates/js/ckfinder/userfiles/files/19303774426.pdfIn PDF document text
    • http://sinara.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/16133ae6dbe025---90539989030.pdfIn PDF document text
    • https://ardiinerkh.mn/uploads/userfiles/files/95714288589.pdfIn PDF document text
    • https://stef-nancy.fr/upload/document/fowizoz.pdfIn PDF document text
    • https://institut-arabe.org/ckfinder/userfiles/files/15158585794.pdfIn PDF document text
    • https://topinsolventa.ro/userfiles/file/12374962557.pdfIn PDF document text
    • http://loaamtran.vn/files/usersfiles/files/botudivokaguxedidopuf.pdfIn PDF document text
    • https://delphin-restaurant.com/ckfinder/upload/files/vofovisuzabuzurotoz.pdfIn PDF document text
    • http://studiocastigli.eu/userfiles/files/dovetixomijomuzafalu.pdfIn PDF document text
    • https://chatham-ebenezer.ckdomain.com/uploads/userfiles/files/kusexirenunisojibowogi.pdfIn PDF document text
    • https://acrgruppe.de/userfiles/file/jubolubesamozefo.pdfIn PDF document text
    • https://mclandpin.com/calisma2/files/uploads/vewidimufowilubagegenage.pdfIn PDF document text
    • http://lachambredechos.com/userfiles/file/42052401480.pdfIn PDF document text
    • https://bokaichenyu.com/upload/files/redam.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/Om9ozkHLxGw/uplcv?utm_term=age+of+war+generals+apkPDF 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_off0000eb43.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB43 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010355.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10355 20044 bytes
SHA-256: f91f31cbb4ea342f988df1e901191368a8b885839f1201ed1507612c0ef134be
font_02_sfnt_off000137d0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x137D0 10500 bytes
SHA-256: d9563cab7f87626515c7845f9e737dd255b0b5e5e44ec681b1b997579c08fba0