Malicious PDF — malware analysis report

Static analysis result for SHA-256 9f09d6b3db1089a4…

MALICIOUS

PDF

85.8 KB Created: 2021-09-21 01:02:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 54651c12337e30adcd739a0022d289ef SHA-1: acffe036a48217f8da464efd214906652fdaa2f1 SHA-256: 9f09d6b3db1089a498a64a0068f06ef04e1429d9c3d427ca5cec011514d36fa9
142 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript, which is a common technique for executing malicious code within PDF documents. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates the PDF is part of a link farm hosted on disposable domains, suggesting a phishing or malware distribution scheme. The presence of numerous external URIs, including one pointing to 'inwebjor.ru', further supports this, as these are likely used to redirect users to malicious sites or download further payloads. The ML classifier and ClamAV detection strongly indicate malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

Heuristics 7

  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://inwebjor.ru/uplcv?utm_term=vn+video+editor+pro+mod+apk PDF link annotation
    • http://meadescafe.com/userfiles/file/6909614172.pdfIn PDF document text
    • http://artemon.nl/userfiles/file/najigebivaxevox.pdfIn PDF document text
    • http://www.lbtfilm.com/uploads/files/8285143851.pdfIn PDF document text
    • http://smartraoptics.com/fck_filemanager_upload/file/zavefunitojunudogideval.pdfIn PDF document text
    • http://kunas.lt/app/webroot/uploads/files/18309966240.pdfIn PDF document text
    • http://studiobaliva.eu/userfiles/files/rovijurebikuxokewef.pdfIn PDF document text
    • https://kaptenhoki.net/contents/files/dibesunamugafuguzipimir.pdfIn PDF document text
    • http://inggeo.eu/userfiles/files/49686949063.pdfIn PDF document text
    • http://baraanduliaptti.org/userfiles/file/wajavexonifewi.pdfIn PDF document text
    • https://backcountryplayground.com/wp-content/plugins/super-forms/uploads/php/files/73ecd19ba4bfa846fd3cb4a856c021ae/muwinenukisemi.pdfIn PDF document text
    • http://www.ernakulamarchdiocese.org/www/js/ckfinder/userfiles/files/tugulonewezelopasuriweg.pdfIn PDF document text
    • http://eventechsite.com/files/files/12844999568.pdfIn PDF document text
    • https://nacituran.com/userfiles/file/68481988138.pdfIn PDF document text
    • http://gasthaus-steinkirchen.de/img/editor/file/28194217202.pdfIn PDF document text
    • https://sokole-tps.pl/userfiles/file/91626524436.pdfIn PDF document text
    • http://www.bash.cl/media/file/kalojosigemadapo.pdfIn PDF document text
    • https://kominove-centrum.cz/media/files/file/74720859304.pdfIn PDF document text
    • http://www.ondebiz.com/userfiles/file/40087912476.pdfIn PDF document text
    • http://cssh.es/img/file/46793204468.pdfIn PDF document text
    • http://azstorestudio.com/uploads/files/jujugibomorimiriwosotun.pdfIn PDF document text
    • http://avandcie-energy.fr/ckfinder/userfiles/files/ferikejovubiwujeb.pdfIn PDF document text
    • http://dansecyr.ca/pdf/file/gopibib.pdfIn PDF document text
    • https://akdenizokullari.k12.tr/wp-content/plugins/super-forms/uploads/php/files/ce9dp27ngjvdifkkorbb0md86l/rofonodakodoj.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_off0000e99e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE99E 10464 bytes
SHA-256: a747c404ae65dbb69e0374b17c3e02d5a29285116bb6fe00ac2440e6f9af2a71
font_01_sfnt_off0001015b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1015B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001196d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1196D 18484 bytes
SHA-256: a699c743ded2f5ac0118e8bae24c0c2ae11ddec18eb5c5af4cbceb5268acc30d