Malicious PDF — malware analysis report

Static analysis result for SHA-256 412d5c5f090eff74…

MALICIOUS

PDF

81.0 KB Created: 2021-09-14 01:30:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 7b0f4f017bcb9d738fe45900cd8ea815 SHA-1: 2a70da1f40e1d7e82a7fc9a2864686dcb3158ff9 SHA-256: 412d5c5f090eff74b8b2cf5fb80f2715e5a0a77677d9d14a6b32f537a3174772
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The heuristic analysis revealed it functions as a link farm, embedding a large number of URLs pointing to disposable hosting, a common tactic for phishing or distributing further malware. While no scripts were explicitly extracted, the PDF structure and embedded URIs suggest it's designed to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://synerhu.ru/uplcv?utm_term=cafe+games+android PDF link annotation
    • https://oreopay57.com/ckfinder/userfiles/files/jeguralurazikuxisav.pdfIn PDF document text
    • https://zivotzaokny.eu/res/file/mulovujagoruwetexugol.pdfIn PDF document text
    • https://webrekruit.com/php_codes/Scott/VieauAssociates/code/userfiles/file/geratariwunepovudig.pdfIn PDF document text
    • http://datacomsystems.cz/userfiles/file/26108121190.pdfIn PDF document text
    • http://www.mearesandassociatesllc.com/siteuploads/editorimg/file/91313408252.pdfIn PDF document text
    • http://www.detskaoptika.cz/ckfinder/userfiles/files/fubibabiwatusub.pdfIn PDF document text
    • http://asclyziarskyklub.sk/userfiles/file/3851176477.pdfIn PDF document text
    • http://thienthaopc.com/upload/FCK/file/37335853817.pdfIn PDF document text
    • http://www.birapart.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613346644de1a---noradurilun.pdfIn PDF document text
    • http://www.louisianarebarcontractor.com/editorimg/file/10394940263.pdfIn PDF document text
    • http://tetrafluoro.com/upload/files/33216768336.pdfIn PDF document text
    • http://dichvumucin.com/upload/ckupload/files/68225698980.pdfIn PDF document text
    • http://kfoodntea.com/dataroom/file/rubum.pdfIn PDF document text
    • http://maudchristan.nl/ckfinder/userfiles/files/83290119243.pdfIn PDF document text
    • https://ceccarmehedinti.ro/userfiles/file/zerotiraweruvifezevef.pdfIn PDF document text
    • https://ymvii.com/admin/upload/files/guxaw.pdfIn PDF document text
    • http://aligokdemir.com/resimler/files/baweweraromixipagitejuk.pdfIn PDF document text
    • http://beergolfers.com/blog/images/file/jinanuzajivo.pdfIn PDF document text
    • http://dobre-jaja.com/Upload/file/sapolanizu.pdfIn PDF document text
    • http://ayurveda-shiatsu-nice.com/upload/files/48016929387.pdfIn PDF document text
    • http://yey.uw52.com/upload/files/pazeluwaluvusijoja.pdfIn PDF document text
    • http://clinton.abwingsmd.com/uploads/files/94611592663.pdfIn PDF document text
    • https://inprovitargentina.com/ckfinder/userfiles/files/lojinido.pdfIn PDF document text
    • https://gift-edu.ru/wp-content/plugins/super-forms/uploads/php/files/d700948f9095c8d1eedd82e12fb0f648/bafat.pdfIn PDF document text
    • http://degeninhotel.ru/admin/ckfinder/userfiles/files/ferofunalejugenimivev.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_off0000db73.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB73 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f385.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF385 16588 bytes
SHA-256: a6f821b9b376f4451c2e6922b5d92fece5ba082bb95e1ec668bd67290878e1cd
font_02_sfnt_off00011e4c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11E4C 10584 bytes
SHA-256: d8d0e5740ba8bdcd58999272f9e5444ef321a8e51b8a4c25cc0883c39a7b8feb