Malicious PDF — malware analysis report

Static analysis result for SHA-256 9450d90dd00ec429…

MALICIOUS

PDF

81.8 KB Created: 2021-09-19 15:43:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 841512867c3cbad33e2d039a1b02668b SHA-1: dbda50c16c1cc7404f27946aa261bb78aa87fda2 SHA-256: 9450d90dd00ec4292d76f87f93ae20dafb36dbfeb31d652661afce44b76b1023
174 Risk Score

Malware Insights

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

The PDF contains heuristics indicating it is a link farm and a lure for browser extension installation, suggesting a social engineering attack. The ClamAV detection and ML classifier further support its malicious nature. While no scripts were directly extracted, the presence of embedded URLs and the nature of the heuristics point towards a phishing or malware delivery attempt, likely involving a second-stage download.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

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
  • 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.
  • 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 http://studiocinti.eu/userfiles/files/geduwazaxesevu.pdf In PDF document text
    • http://ke-sen.com/userfiles/file/1632001313.pdfIn PDF document text
    • http://www.derbysignandgraphics.com/uploads/file/6895643526.pdfIn PDF document text
    • https://rosebankprimary.co.za/inc/ckfinder/userfiles/files/fuvefekimogosawet.pdfIn PDF document text
    • http://evola.it/userfiles/files/80150449539.pdfIn PDF document text
    • https://www.truesdalepainting.com/wp-content/plugins/formcraft/file-upload/server/content/files/16133903585aed---57882746831.pdfIn PDF document text
    • http://wasserentkalkung.at/ckfinder/userfiles/files/1996406824.pdfIn PDF document text
    • http://z500.si/files/39417329418.pdfIn PDF document text
    • http://galaxyjewel.cn/uploadfile/files/sozonosududokumesede.pdfIn PDF document text
    • https://rajaunited.com/contents/files/pokuvip.pdfIn PDF document text
    • http://artospace.com/pics/file/58651881837.pdfIn PDF document text
    • https://ssmahavidyalaya.org/lion/uploadedfiles/fck/files/file/sosomubafagogu.pdfIn PDF document text
    • http://w-mill.jp/images/file/buzodopimibimanirukavowi.pdfIn PDF document text
    • http://thebookmarkcafe.com/uploads/files/31627783721.pdfIn PDF document text
    • http://tipiland.net/upload/file/92909430974.pdfIn PDF document text
    • http://studiotecnicodambra.eu/userfiles/files/97252924467.pdfIn PDF document text
    • http://pekbdt.com/filespath/files/20210914074842.pdfIn PDF document text
    • http://antansconstructions.com/ckfinder/userfiles/files/rewenadedefefumow.pdfIn PDF document text
    • https://lyonsinn.com/nbloom/fckuploads/file/2689811310.pdfIn PDF document text
    • http://gamax-moto.cz/data/dokumenty/27840542745.pdfIn PDF document text
    • http://tsg-vaganovskoe.ru/ckfinder/userfiles/files/60469361394.pdfIn PDF document text
    • http://designpavelzapletal.cz/files/file/wosik.pdfIn PDF document text
    • https://kibledergisi.net/resimler/files/86599114984.pdfIn PDF document text
    • http://cana.vn/uploads/userfiles/file/giwiso.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3vuEKuznOb8/uplcv?utm_term=chal+mera+putt+online+watchPDF 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_off0000da9d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA9D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f2af.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF2AF 17940 bytes
SHA-256: 59f80b4d4f88384be0cf1083fd943752edf99c85c63fe3fde8d3003f60677d09
font_02_sfnt_off000121a6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x121A6 10688 bytes
SHA-256: 455e07ce8504d7c3d8efebdb8e79069cfa531954f63198c6c7123261ec9a29b0