Malicious PDF — malware analysis report

Static analysis result for SHA-256 f6b37add0a9a180c…

MALICIOUS

PDF

74.3 KB Created: 2021-09-19 20:29:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 435eaac748084e2788d29121c7f57262 SHA-1: eb456a2659c727c62d26aef19789a721647d006f SHA-256: f6b37add0a9a180c4c3920e4f8c427803d45f172cc6496ebc8187c0977d90fd5
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The file was detected as malicious by ClamAV and an ML classifier, and exhibits characteristics of a link farm with numerous external URIs. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a high volume of links to potentially disposable hosting, suggesting a phishing or malware distribution scheme. Although no scripts were explicitly extracted, the PDF structure and numerous URLs point towards an attempt to lure users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9837

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.
  • 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://pistant.ru/uplcv?utm_term=apps+ko+chupane+wala+apps PDF link annotation
    • https://pixel.bg/img/file/19932592863.pdfIn PDF document text
    • http://envisystem.com/upload/userfile/files/36723379052.pdfIn PDF document text
    • http://musicpark-live.de/userfiles/file/wexuzizogabi.pdfIn PDF document text
    • https://multimetrics.com/ckfinder/userfiles/files/97068055233.pdfIn PDF document text
    • http://imagespa.mx/wp-content/plugins/formcraft/file-upload/server/content/files/1613682a70d7c7---3953224960.pdfIn PDF document text
    • http://qbcar.ru/ckfinder/userfiles/files/99743656066.pdfIn PDF document text
    • http://bharatdarshan.net/rgroup/ckfinder/userfiles/files/sixudirofobisetibupuk.pdfIn PDF document text
    • http://winecellarkeeper.com/ckfinder/userfiles/files/xepanopo.pdfIn PDF document text
    • https://cortemadera.com/wysiwygfiles/file/gisidokobamigomowad.pdfIn PDF document text
    • http://shiokuda1.com/contents/files/40554839629.pdfIn PDF document text
    • https://dailyiat.com/html_upload/file/48151879419.pdfIn PDF document text
    • https://pbpkrosno.com/fckfile/98468602713.pdfIn PDF document text
    • http://jr.ac.th/ckfinder/userfiles/files/5349424293.pdfIn PDF document text
    • https://whatproperty.ng/ckfinder/userfiles/files/dejezixitowofilivunego.pdfIn PDF document text
    • https://crownprolaw.com/userfiles/Proj_Name/files/jegosak.pdfIn PDF document text
    • http://www.marcado.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16140912316596---mijunipumewevirowofifuk.pdfIn PDF document text
    • http://vln.nl/files/file/voxibenurapopedo.pdfIn PDF document text
    • http://hrmconsulting.biz/upload/files/76562657015.pdfIn PDF document text
    • https://www.shropshirefurniture.co.uk/admin/ckfinder/userfiles/files/beguwakosadesavizu.pdfIn PDF document text
    • https://jesssmithtri.com/jesssmith/ckfinder/userfiles/files/ranagobol.pdfIn PDF document text
    • https://cnc-ar.ro/files/file/xuzoxikivipewenok.pdfIn PDF document text
    • https://bienenaktuell.com/sites/bienenaktuell.com/files/file/13204736581.pdfIn PDF document text
    • http://cafemsoffice.com/userfiles/files/65615028500.pdfIn PDF document text
    • http://xn--c1aejbdnke.xn--p1ai/admin/ckfinder/userfiles/files/totefunufumobuda.pdfIn PDF document text
    • https://blagoustroystvo24.ru/ckfinder/userfiles/files/51137180631.pdfIn PDF document text
    • http://osteriadelcampanile.com/userfiles/files/64194209417.pdfIn PDF document text
    • http://cosmoscm.com/contents/files/66813148640.pdfIn PDF document text
    • https://jagamimpi.info/contents/files/60075233239.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_off0000b95f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB95F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d176.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD176 10440 bytes
SHA-256: 25c7a8ed625a01cefda55f8b2ebbf357afc32d67ceeb708a8823fe8d7c01d942
font_02_sfnt_off0000e938.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE938 18880 bytes
SHA-256: b38d28a9da3387b402167447b15d70167968e469dd8f5bde33b1f8e9c3e90b03