Malicious PDF — malware analysis report

Static analysis result for SHA-256 22aa4a2b6eec717f…

MALICIOUS

PDF

75.0 KB Created: 2021-09-19 08:56:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-21
MD5: 84076561a0d5319ee7cee4267f5aedbe SHA-1: 4c223c2020793075092e4e3b51d138c8fc8c2991 SHA-256: 22aa4a2b6eec717fd8374581d2825ba693ff1b7343135b71a9aa6585d6a09273
134 Risk Score

Malware Insights

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

The sample is a PDF file flagged by ClamAV as Pdf.Phishing.Trojan and by an ML classifier with high confidence. It contains embedded JavaScript and numerous external URIs, many of which point to disposable hosting and are structured as link farms. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic indicates a deliberate attempt to create a large number of links, suggesting a phishing or malware distribution campaign. The embedded JavaScript likely facilitates the redirection to these malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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
  • 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
  • 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://laborke.ru/uplcv?utm_term=developer+option+in+phone PDF link annotation
    • http://nbc.com.vn/ckfinder/userfiles/files/10986950203.pdfIn PDF document text
    • http://esoftland.com/userfiles/file/pugaladakawo.pdfIn PDF document text
    • http://tgtech-auto.com/userfiles/file/suxovokogopotogoparazoj.pdfIn PDF document text
    • http://savemaxint.com/files/file/20001301811.pdfIn PDF document text
    • https://wic-net.com/userfiles/file/tesukuninidosipigewiname.pdfIn PDF document text
    • http://hz-kontejnery.cz/ckfinder/userfiles/files/zitajuko.pdfIn PDF document text
    • https://www.rongoldmanlaw.com/system/js/back/ckfinder/userfiles/files/sijarawulitiguz.pdfIn PDF document text
    • http://idroter.org/userfiles/files/53188915853.pdfIn PDF document text
    • https://www.gurgy.net/ckfinder/userfiles/files/81143954709.pdfIn PDF document text
    • https://anmoul.com/userfiles/file/89423134193.pdfIn PDF document text
    • https://debden.org/userfiles/file/In PDF document text
    • https://gulfcans.com/home/madarmun/public_html/gulfcans/images/bulk_images/files/gobifovibupofu.pdfIn PDF document text
    • http://peggylittlelawoffice.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/81111603800.pdfIn PDF document text
    • http://noithatdangcap.vn/app/webroot/uploads/files/49209931809.pdfIn PDF document text
    • http://reyazahmad.bscsaoner.in/ckfinder/userfiles/files/7107884606.pdfIn PDF document text
    • https://ksuskalology.com/images/file/nuzexabevapoko.pdfIn PDF document text
    • http://emiem.pl/public/upload/ckfinder/userfiles/files/nadidefuverofuruja.pdfIn PDF document text
    • https://fjordancv.info/wp-content/plugins/super-forms/uploads/php/files/8e91c79b400a563d4cf8bd9f7eaa3465/bivirotubax.pdfIn PDF document text
    • http://hanboo.cn/Uploads/file/2021090807051570554.pdfIn PDF document text
    • http://wsystem.sk/userfiles/files/kilutilot.pdfIn PDF document text
    • http://sumosushingrill.com/uploads/files/47993890756.pdfIn PDF document text
    • http://assushop.com/userfiles/assushop.com/file/xujapebixapuraluwabejurad.pdfIn PDF document text
    • http://bagliodeimille.it/userfiles/files/89841412710.pdfIn PDF document text
    • http://seibyou-koujien.com/files/files/movosasoda.pdfIn PDF document text
    • http://cheers-gifts.com/userfiles/62546137521.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_off0000c58c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC58C 10084 bytes
SHA-256: e200c459228c631faad39c0de36856f9c7e514ce5dbb3aa8cf8dbdb6b5e55b10
font_01_sfnt_off0000dbde.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDBDE 16476 bytes
SHA-256: 58bf0979ac7daebbafc8d600d04917eee0fa7c3ff9f4c5d2fa32d6b496fa821f
font_02_sfnt_off0001065f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1065F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1