Malicious PDF — malware analysis report

Static analysis result for SHA-256 b422fd9707c7b542…

MALICIOUS

PDF

83.6 KB Created: 2021-09-18 18:57:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: f1224a2dd0c5f2868fafa683cdf9a9c1 SHA-1: 9914468fdfa901342bf5fc38f2742a5486f33973 SHA-256: b422fd9707c7b54299271644085f33cafdf80177baeb47dff3261b440c44ec39
166 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

This PDF file was flagged as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The 'SE_BROWSER_INSTALL_LURE' heuristic suggests the document is designed to trick users into installing a fake browser update or extension. While no scripts were directly extracted, the presence of external URIs and the overall structure point towards a phishing or malware delivery mechanism, likely involving a social engineering pretext to download and execute a secondary payload.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://huntic.ru/uplcv?utm_term=pdf+viewer+chrome+android PDF link annotation
    • http://www.egavilanes.com/ckfinder/userfiles/files/83620431000.pdfIn PDF document text
    • http://officeharbor.com/pdtInfo/legulupefufiriruz.pdfIn PDF document text
    • https://ecowaytechnologies.com/ckfinder/userfiles/files/gijavanuxupufekewurizo.pdfIn PDF document text
    • http://unternehmensberatung-hegenbarth.com/userfiles/file/piximuwisasapakozuzudo.pdfIn PDF document text
    • http://tageedesign.com/ssmpt/documents/file/kefaxo.pdfIn PDF document text
    • http://businessvaluationapp.com/fck_files/file/67164376740.pdfIn PDF document text
    • https://perfecthospital.net/ckfinder/userfiles/files/pumusikaboga.pdfIn PDF document text
    • https://baongochoa.com/upload/file/jigijosodo.pdfIn PDF document text
    • http://krindustria.com.br/site/wp-content/plugins/formcraft/file-upload/server/content/files/1613bcaae6b023---dogiko.pdfIn PDF document text
    • https://ashleymongolia.mn/uploads/files/86842224272.pdfIn PDF document text
    • http://amuseonline.com/absite/userfiles/file/pekota.pdfIn PDF document text
    • https://prestinireedcorp.com/userfiles/files/77313016526.pdfIn PDF document text
    • http://life-worldwide.org/assets/uploads/files/45081939968.pdfIn PDF document text
    • http://stkvn.ru/wp-content/plugins/super-forms/uploads/php/files/ff582a3ea16e4e834c7b9f841ea6278e/76748956471.pdfIn PDF document text
    • https://digireg.se/upload/93822398686.pdfIn PDF document text
    • https://kamionosnyelvlecke.hu/userfiles/file/zosedo.pdfIn PDF document text
    • http://nujhimachal.in/img/uploads/files/rinegopopinuzonazazofu.pdfIn PDF document text
    • https://www.shropshirefurniture.co.uk/admin/ckfinder/userfiles/files/1172313780.pdfIn PDF document text
    • http://cross-winds.in/upload/contents/images/images/devupadaxiwudodilibosi.pdfIn PDF document text
    • https://izometal.net/mm/file/55986992330.pdfIn PDF document text
    • http://loveperfectionschool.com/upload/file/gotuniji.pdfIn PDF document text
    • http://mko-yug.ru/wp-content/plugins/super-forms/uploads/php/files/6b41ebf2504cd51bcfaca747b72a5c1f/mopevolozasetusoja.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_off0000e166.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE166 18024 bytes
SHA-256: 88b49e4957d6d9e5f7ecaba59c5dc16aef2b214befa9925feb7d705d3b421b7c
font_01_sfnt_off00011104.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11104 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001291b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1291B 10584 bytes
SHA-256: 5bf3cb2acbd6cdfe7808d9a7ccf647b768d2b0184e7f4cf4f31c161a25eeefb0