Malicious PDF — malware analysis report

Static analysis result for SHA-256 c33db9a0e73517ee…

MALICIOUS

PDF

81.4 KB Created: 2021-09-09 17:43:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 045570429a0ce84637a5ca5547e70490 SHA-1: a992cff8cb33a4d0a3f202dcc8870d651ce0040a SHA-256: c33db9a0e73517ee8bd023d96b47660eb7236f5bc7f866fc6945b75e202af1a9
206 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious File

The PDF document employs social engineering tactics, specifically a lure to install a browser extension or update, which is a common method for credential harvesting or malware installation. The ML classifier and ClamAV detection strongly indicate malicious intent. The document also contains numerous URLs, including one that appears to be a link farm, suggesting it is part of a larger phishing infrastructure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9949

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • MFA / one-time-code harvesting lure high SE_MFA_LURE
    Document asks for a one-time code, authenticator approval, or MFA confirmation — consistent with credential phishing kits that steal session tokens or abuse multi-factor authentication
  • Browser extension / update installation lure high SE_BROWSER_INSTALL_LURE
    Document tells the user to install a browser extension, plugin, viewer, or browser update to view content — a common social-engineering path for credential theft and malware installation
  • 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.
  • 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://irlanc.ru/uplcv?utm_term=how+to+copy+your+contacts+from+android+to+iphone PDF link annotation
    • http://hexindechem.com/upload/files/xemiju.pdfIn PDF document text
    • https://bursakaynak.net/userfiles/file/30714568147.pdfIn PDF document text
    • http://csaladiegyteruautok.hu/userfiles/files/59198631251.pdfIn PDF document text
    • http://wahluenfty.com/userfiles/gudomuset.pdfIn PDF document text
    • http://texinpack.com/uploadfile/file///2021090716065147.pdfIn PDF document text
    • http://epodhajska.eu/UserFiles/File/17042976289.pdfIn PDF document text
    • https://alwaysthesame.pt/site/upload/file/fubukudukada.pdfIn PDF document text
    • http://feriaalainversa.com/uploaded/files/lewogo.pdfIn PDF document text
    • http://asckhn.com/acskhn/userfiles/file/39229959104.pdfIn PDF document text
    • https://copperscraphandlers.com/ckfinder/userfiles/files/gokeketeze.pdfIn PDF document text
    • http://longarmquiltingacadamy.com/fckeditor/userfiles/file/sibar.pdfIn PDF document text
    • http://gaia-onlus.org/userfiles/file/levowapetadulimaxozovojuz.pdfIn PDF document text
    • https://beamstraffic.com/amb/userfiles/file/xiramuba.pdfIn PDF document text
    • https://audreyheselmans.com/_files/file/puwavoxufesajixelotif.pdfIn PDF document text
    • http://neurooperations.com/ckfinder/userfiles/files/jojinotamivobuwegudeg.pdfIn PDF document text
    • https://dfa-finanz.de/wp-content/plugins/formcraft/file-upload/server/content/files/161378f10db123---46948566728.pdfIn PDF document text
    • https://mission4recruitment.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613044b66bcf0---wetedoweta.pdfIn PDF document text
    • https://yifff.se/userfiles/file/14135378245.pdfIn PDF document text
    • https://puntodeplacer.com/userfiles/file/64601825414.pdfIn PDF document text
    • http://valkexclusief.reviews/app/webroot/files/userfiles/files/5292130730.pdfIn PDF document text
    • https://adamant54.ru/userfiles/files/31808927361.pdfIn PDF document text
    • https://istanbulbalbir.com/upload/ckfinder/files/80394845459.pdfIn PDF document text
    • http://vet-arrighicolangelicristilli.eu/userfiles/files/63075452889.pdfIn PDF document text
    • http://finadev-groupe.com/userfiles/file/59245759106.pdfIn PDF document text
    • http://theclubburger.com/uploads/files/kemozodisafu.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_off0000da58.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA58 16916 bytes
SHA-256: 9c69d951536ec1dffd2bd3202ef2c7fed702ad33243cbdf25a14a8b24368474f
font_01_sfnt_off0001061b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1061B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011e32.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11E32 11132 bytes
SHA-256: d3035e456fbf3f123204d2e65f834b1835d3a4a942d960f11044e000454b8fa4