Malicious PDF — malware analysis report

Static analysis result for SHA-256 6f3ae88e41bd10f0…

MALICIOUS

PDF

73.7 KB Created: 2021-09-18 05:10:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 1561088218c43436879038cfa2c7f167 SHA-1: 94175ff19bb452bdd9ec36f1c60cc9f5b79573ba SHA-256: 6f3ae88e41bd10f0fbb855081c9e58c68c5387b26ab1054b7e4206f63ac3fbf3
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' suggests the document is part of a link farm designed to distribute malware. The presence of numerous external URIs, including one pointing to 'coretry.ru', further supports the phishing and malware distribution vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://coretry.ru/uplcv?utm_term=one+key+root PDF link annotation
    • https://www.golaw.net/wp-content/plugins/formcraft/file-upload/server/content/files/16143e82f10a82---lonedafefifiremu.pdfIn PDF document text
    • http://boki.hu/editor_up/82485011498.pdfIn PDF document text
    • https://brigitte-farner.ch/userfiles/files/6257254001.pdfIn PDF document text
    • https://sipare.com.ar/wp-content/plugins/super-forms/uploads/php/files/otu92tn1tojgpbn4krpmvtn4fb/tobokokugarejatufajigokoz.pdfIn PDF document text
    • http://opuspointpartners.com/ckfinder/userfiles/files/lavujunil.pdfIn PDF document text
    • https://momsgardenfoods.com/ckfinder/userfiles/files/pubagazupa.pdfIn PDF document text
    • http://www.klimavill.com/data/editorfile/waxufeveba.pdfIn PDF document text
    • http://9jamail.com/FCKeditor/editor/filemanager/connectors/userfiles/file/direp.pdfIn PDF document text
    • http://liluby.com/upload/file/xujelevumivudifarirodekeb.pdfIn PDF document text
    • http://startent.ru/SITE/files/editor/file/dumobewabesu.pdfIn PDF document text
    • https://tradingphrases.com/userfiles/files/naxakaxabigudunodurugalok.pdfIn PDF document text
    • https://indiantalentjunction.com/milan/media/10015982527.pdfIn PDF document text
    • http://marienoellebermond.com/img/uploaded/file/49062682611.pdfIn PDF document text
    • http://bamboomfi.com/htdocs/cljr/data/files/35435292819.pdfIn PDF document text
    • http://st-communications.com/ckfinder/userfiles/files/fajewumi.pdfIn PDF document text
    • http://sitarofindiamd.com/userfiles/file/pupedilejalabopelemefo.pdfIn PDF document text
    • https://www.alliance-educationsexuelle.ch/ck/ckfinder/userfiles/files/37037943711.pdfIn PDF document text
    • http://zopos.zohukum.com/ckfinder/userfiles/files/pagitasabekura.pdfIn PDF document text
    • http://ivelinabozilova.com/userfiles/file/83518440989.pdfIn PDF document text
    • http://www.examnotice.in/uploads/files/68017404923.pdfIn PDF document text
    • http://kondicionery-ivanteevka.ru/upload_picture/file/jowixizodoneviniko.pdfIn PDF document text
    • http://khiensa.com/UserFiles/File/pokaxumasovedaweziluxojug.pdfIn PDF document text
    • http://cnc-soustruzeni.cz/files/file/patapiwikelavufagogewenof.pdfIn PDF document text
    • http://euro-ex.net/images/blog/file/wurodufuluw.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_off0000c0b6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC0B6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d8c8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD8C8 16544 bytes
SHA-256: 65cf6f5fc987974a532e79d11d4b12486d2602ee14fd80b68762ec24dd1aaba9
font_02_sfnt_off000103c0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x103C0 9864 bytes
SHA-256: 1faa0b86d58771df5ab36e169903a06e42573b0100636977813b6e2520b57208