Malicious PDF — malware analysis report

Static analysis result for SHA-256 8cbfce11fb80a714…

MALICIOUS

PDF

86.9 KB Created: 2021-09-22 11:22:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 0625dbd73d752bf6aff15bbe67f221d2 SHA-1: 5aab7962aa81cb09fbe52a6e437f4d6940931434 SHA-256: 8cbfce11fb80a714672d605ff15ac19a12e7edaff1fd96268ff637b2a9ff43b9
156 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to multiple compromised CMS upload directories, indicating an attempt to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly suggest malicious intent. The presence of numerous links on disposable or compromised hosting further supports this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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
  • 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.
  • 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 http://vivo-mebel.ru/upload/file/wavifoxemoxejiv.pdf In PDF document text
    • http://biomehl.com/images/content/files/zatonulumebamoxes.pdfIn PDF document text
    • http://thevisionkharj.com/userfiles/files/lelijeranatezabed.pdfIn PDF document text
    • https://www.advids.co/wp-content/plugins/formcraft/file-upload/server/content/files/1613d369ff2f70---kematove.pdfIn PDF document text
    • https://www.phoenixdentalacademy.co.uk/wp-content/plugins/super-forms/uploads/php/files/f53fb19c75585f5ab8a182d889e2b96d/muwinafotadugikovisilu.pdfIn PDF document text
    • http://gamjagolla.com/uploads/files/koxusozuru.pdfIn PDF document text
    • http://recko.ru/ckfinder/userfiles/files/87448185014.pdfIn PDF document text
    • https://branchennachweis.eu/userfiles/file/razinadodotuxe.pdfIn PDF document text
    • https://people11people.com/uploads/File/bunukogagekena.pdfIn PDF document text
    • https://master.plus/wp-content/plugins/super-forms/uploads/php/files/a23081305907f87a6ba909b5d328bb84/rirefekuwuzilod.pdfIn PDF document text
    • http://www.blueoak.fr/image/file/44790404639.pdfIn PDF document text
    • https://magatek.com/documents/file/nokaposokukodafure.pdfIn PDF document text
    • https://rwd1.thadv.com/upload/files/xopulo.pdfIn PDF document text
    • http://tulga.ru/editor/files/63451500822.pdfIn PDF document text
    • http://clingac.com/d/files/xebosifeti.pdfIn PDF document text
    • https://faguaflowers.com/images/admin/file/xejolamaga.pdfIn PDF document text
    • http://www.onlinenieuwsbriefversturen.nl/gebruikers/afbeeldingen/91467411514.pdfIn PDF document text
    • http://imhyuk.com/imhyukeditor/userfile/file/6485555269.pdfIn PDF document text
    • http://adanateknikservis.web.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1613f704931f4e---suvesew.pdfIn PDF document text
    • http://myhomeinparis.com/userfiles/files/gaxoposagixomixo.pdfIn PDF document text
    • http://sanarina.de/ckfinder/userfiles/files/30885475648.pdfIn PDF document text
    • https://iieng.org/editor/ckfinder/userfiles/files/fugamutezofa.pdfIn PDF document text
    • http://www.yoko-ono.be/images/userfiles/file/12685087953.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/fzgW7-mxBc0/uplcv?utm_term=sad+quotes+on+love+hurtsPDF link annotation
    • 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_off0000ed95.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED95 10640 bytes
SHA-256: b38ed51be8b0201bfeed921abcf6c32ed05e866e4b3dec92d6dfbaff6f0e0aec
font_01_sfnt_off000105b2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x105B2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011dc4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11DC4 18616 bytes
SHA-256: 84acf68473428e6f2bb078fc1ffd0ced307c62f4af595106449d211ebca61c53