Malicious PDF — malware analysis report

Static analysis result for SHA-256 f1d6222420116e53…

MALICIOUS

PDF

80.4 KB Created: 2021-09-22 21:46:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: e0890413665005d857da84a6d0801cfd SHA-1: 02715296897251f60fae4dbe9c461b7a53e557ba SHA-256: f1d6222420116e5386227dc186f491bc8a1362148e5ba298f1579278852b213c
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF containing embedded JavaScript and numerous external URIs, many of which are hosted on compromised or disposable domains. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates the document's primary purpose is to act as a link farm, likely directing users to phishing sites or further malware. The embedded JavaScript, while not fully analyzed due to obfuscation, is a common vector for exploiting PDF vulnerabilities or initiating malicious actions.

Machine Learning

  • Nyx PDF Classifier malicious score 0.7970

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
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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.
  • External URI info PDF_URI
    PDF contains an external URL action
  • PDF differential parser failed info PDF_DIFFERENTIAL_PARSE_FAILED
    The cross-check parser (pdfminer.six) failed on this file: PDF differential parser failed: PDFSyntaxError. Static heuristics still ran and any of their findings above are valid; only the differential cross-check signal is missing.
  • 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://coretry.ru/uplcv?utm_term=java+jdk+android+studio PDF link annotation
    • https://luyenthitoeic.info/userfiles/file/65282822971.pdfIn PDF document text
    • http://kibbkw.com/uploads/files/matibukiva.pdfIn PDF document text
    • https://lokmangal.co.in/wp-content/plugins/super-forms/uploads/php/files/61182e234f9b3dbdf6441c205239031d/keroluvuw.pdfIn PDF document text
    • https://www.kiteschule-kiel.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613ee04321540---99979693804.pdfIn PDF document text
    • http://fitsiluet.cz/data/file/49826064485.pdfIn PDF document text
    • https://rt-totaalafbouw.nl/userfiles/file/zupowazamaforavowenozex.pdfIn PDF document text
    • https://pabausa.org/wp-content/plugins/formcraft/file-upload/server/content/files/161485c8e2b9de---77504513912.pdfIn PDF document text
    • https://groupekheidri.com/ckfinder/userfiles/files/fizirurivopaporuwaxi.pdfIn PDF document text
    • http://thesnowmanicecream.com/ckfinder/userfiles/files/nabubukapulutazidubi.pdfIn PDF document text
    • https://piataafacerilor.ro/app/webroot/files/userfiles/files/97993618877.pdfIn PDF document text
    • https://anakaygame.net/calisma2/files/uploads/woxaradopekarovosodunolim.pdfIn PDF document text
    • https://greenturtleproductions.com.au/wp-content/plugins/super-forms/uploads/php/files/dabfb06968dfbf6bf11f1bdf08d01135/48103937103.pdfIn PDF document text
    • http://baraanduliaptti.org/userfiles/file/renozamabe.pdfIn PDF document text
    • https://penmypoem.com/new/admin/uploadfiles/file/rugojewejutajerulubege.pdfIn PDF document text
    • http://www.fattyweng.com.sg/wp-content/plugins/formcraft/file-upload/server/content/files/16144111074ef4---44367142765.pdfIn PDF document text
    • http://www.stsmcc.org/www/js/ckfinder/userfiles/files/popupuligosufegowegovisad.pdfIn PDF document text
    • http://ricarda-allegra.de/userfiles/file/29888757689.pdfIn PDF document text
    • http://rudolphi.nu/userfiles/file/nuvigelule.pdfIn PDF document text
    • https://webmedcentralplus.com/userfiles/file/zuloputivipaw.pdfIn PDF document text
    • https://confeccionesruiz.cl/UserFiles/File/49871442162.pdfIn PDF document text
    • https://norservis.info/files/files/47344031545.pdfIn PDF document text
    • https://arte-salon.ru/upload_picture/buwirerirapoz.pdfIn 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_off0000dbaf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDBAF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f3c1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF3C1 20048 bytes
SHA-256: 936da416d316921473a9b315a0d59ef8b2dc03f17f841891f9b1430c316b2c94
font_02_sfnt_off00012849.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12849 10440 bytes
SHA-256: 065e00df331c919de3ecff5e553c7d8adb916112216a3c44e9a6933556ffe39e