Malicious PDF — malware analysis report

Static analysis result for SHA-256 3278e574770d31aa…

MALICIOUS

PDF

81.2 KB Created: 2021-09-12 14:16:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 034bb5d4a3e620483088d7fe5abad78a SHA-1: 0f5e1d254eeb97ac3452147ae374fb7d7477fd25 SHA-256: 3278e574770d31aa4b18b424f7fc03798e0c56401cf52cfca498c37542ff15b5
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is identified as malicious by ClamAV and an ML classifier, with multiple heuristics indicating it functions as a link farm on disposable hosting. The embedded URLs, such as https://smidgel.ru/uplcv?utm_term=block+puzzle+play+store, are likely used to redirect users to phishing or malware-hosting sites. Although no scripts were explicitly extracted, the PDF structure and numerous external links suggest an attempt to exploit users via malicious web content, aligning with spearphishing attachment tactics.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

Heuristics 5

  • 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.
  • 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://smidgel.ru/uplcv?utm_term=block+puzzle+play+store PDF link annotation
    • http://cameradungphat.com/uploads/files/tiwejokinegejav.pdfIn PDF document text
    • https://konyaalotaksi.com/userfiles/file/bibuko.pdfIn PDF document text
    • https://euinsuti.ro/app/webroot/files/userfiles/files/93625126729.pdfIn PDF document text
    • https://organicearthfiji.com/documents/file/3849802577.pdfIn PDF document text
    • http://zh-huaxun.com/uploadfiles/files/dipaneguzetuvenofadu.pdfIn PDF document text
    • http://eamenfaraz.com/cache/fck_files/file/kodedoporarew.pdfIn PDF document text
    • https://gencshow.com/upload/ckfinder/files/lisosel.pdfIn PDF document text
    • http://thegioimaychaybo.com/app/webroot/uploads/files/255037355.pdfIn PDF document text
    • https://aristi-trap.com/upload/users/files/divomezow.pdfIn PDF document text
    • https://ddshower.com/ckfinder/userfiles/files/90239356195.pdfIn PDF document text
    • http://cck-brno.cz/ckfinder/userfiles/files/18694155161.pdfIn PDF document text
    • http://zamokugrofa.sk/admin/fckeditor/file/74929126230.pdfIn PDF document text
    • https://doctmcooper.com/userfiles/files/54328581601.pdfIn PDF document text
    • https://studiovizia.com/webroot/img/content/files/ketamapituxiladefimujajus.pdfIn PDF document text
    • http://abwplazaview.com/uploads/files/bizijizebu.pdfIn PDF document text
    • http://ecovn.vn/uploads/news_file/lilupelupobisokewev.pdfIn PDF document text
    • https://kaowei.tw/image/files/20210905_121811.pdfIn PDF document text
    • https://somogyplusz.hu/files/54313620413.pdfIn PDF document text
    • http://hai-bi.com/uploads/files/202109070813033844.pdfIn PDF document text
    • http://studiolauramoschini.it/userfiles/files/diduboxanufodozo.pdfIn PDF document text
    • http://kolaykanal.com/userfiles/files/43547901916.pdfIn PDF document text
    • https://www.hospedeagora.com.br/wp-content/plugins/super-forms/uploads/php/files/qh56vt6droo8b716ktag6f79i2/82200311485.pdfIn PDF document text
    • http://aguito.madteam.net/ckfinder/userfiles/files/81238742636.pdfIn PDF document text
    • http://danguykhoidoanhnghiephp.vn/Upload/files/xalosikon.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_off0000d934.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD934 10592 bytes
SHA-256: bbe885affb8a46e2071e399ade5665474698471efbcd9ce2a56c5e09efa9d854
font_01_sfnt_off0000f1bb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF1BB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000109cd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x109CD 17620 bytes
SHA-256: cb5fbe1b734d262201ae4b670368c0599e13c7a76bdceb7176c156d480aee60c