Malicious PDF — malware analysis report

Static analysis result for SHA-256 92df7c8da52e3d51…

MALICIOUS

PDF

66.5 KB Created: 2021-10-02 12:02:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: e18944b00d51799a0fb7ed432b243d0a SHA-1: 33cc3bf4b985b94540e732340bbbac9aee1fc80b SHA-256: 92df7c8da52e3d512402099e051ad66c0af894aa8cc6ec2fda1e7731fe1811d3
132 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is identified as malicious by ClamAV and exhibits characteristics of a link farm, with numerous URLs pointing to potentially compromised or disposable hosting. The embedded JavaScript stream suggests an attempt to execute code, likely to facilitate redirection or further payload delivery. The presence of compromised CMS upload links further indicates a malicious intent to leverage vulnerable web infrastructure.

Machine Learning

  • Nyx PDF Classifier suspicious score 0.2639

Heuristics 6

  • 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
  • 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://youkuvpn.com/upload/files/gatofubevexixefixedex.pdf In PDF document text
    • http://noahmission.org/dataroom/file/zutekemeboxulox.pdfIn PDF document text
    • https://braintreeclinics.com/app/webroot/img/files/zurupemupibew.pdfIn PDF document text
    • http://mijneigenlift.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1613fac1cb56ca---64803215170.pdfIn PDF document text
    • http://kenshopvn.com/uploads/files/kitogugazitudirowabarap.pdfIn PDF document text
    • http://sakesushilakehavasu.com/uploads/files/jupadagixakazekajam.pdfIn PDF document text
    • http://leylatoprak.com/userfiles/file/28069267469.pdfIn PDF document text
    • http://myxroad.net/upload/userfiles/file///nedanetomevatuwemar.pdfIn PDF document text
    • https://tutorlookup.com/ckeditor/ckfinder/userfiles/files/657346345.pdfIn PDF document text
    • https://stiglic.sk/userfiles/file/newevusazinigus.pdfIn PDF document text
    • http://mayjack.com/upload/files/xezurumiluvi.pdfIn PDF document text
    • http://www.ochoadentalcare.com/tacgestorcontenidos_ochoa/documentos/file/In PDF document text
    • https://truongdongkinh.phapluatvietnam.com/upload/ckupload/files/bunoxupivokuzugup.pdfIn PDF document text
    • http://www.mkkdigital.pt/wp-content/plugins/formcraft/file-upload/server/content/files/1615108049a66c---98356430164.pdfIn PDF document text
    • http://smartickgroup.com/userfiles/76614401229.pdfIn PDF document text
    • https://cicadit.ro/UserFiles/file/nuwavijiwuradotilugiru.pdfIn PDF document text
    • http://soyaksiesta3.com/userfiles/file/9751245974.pdfIn PDF document text
    • http://thongthien.vn/upload/files/33737602551.pdfIn PDF document text
    • https://sandalyecenneti.com/wp-content/plugins/super-forms/uploads/php/files/1rn3tv1hcq4tmdfc73bm0mib5g/97663504238.pdfIn PDF document text
    • http://venusland.vn/app/webroot/img/files/zupalisorugoburoxolek.pdfIn PDF document text
    • https://bloomlight.pl/_bloom/file/66373462410.pdfIn PDF document text
    • http://tanabuauto.com/js/upload/files/35044185838.pdfIn PDF document text
    • http://papierplus.pl/userfiles/file/bopeloxex.pdfIn PDF document text
    • http://daltan.hu/userfiles/file/18390053509.pdfIn PDF document text
    • https://www.novet.de/wp-content/plugins/formcraft/file-upload/server/content/files/16132ee1987450---mozivusakelelunegodub.pdfIn PDF document text
    • https://webmodels.studio/wp-content/plugins/formcraft/file-upload/server/content/files/16148a70a6d920---potalogivonuvafabekujaw.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/YTWXjIUwRh0/uplcv?utm_term=normocytic+red+blood+cellsPDF link annotation
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000b791.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB791 10496 bytes
SHA-256: 87b3ae8348cc9a97ee93bd2aca72c161141b6cb31285dff0278298bb3b0413e3
font_01_sfnt_off0000cf73.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCF73 17044 bytes
SHA-256: 8f3a5617b9b596185b3ff4bd34b4ea90bec88bac4409131c286f4d653bb291a0