Malicious PDF — malware analysis report

Static analysis result for SHA-256 a5a09b760d8a7e05…

MALICIOUS

PDF

77.4 KB Created: 2021-09-09 09:11:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 80ef3bb9606046ad2ba0195c69e5783d SHA-1: e07e05b38983b8a28c07e7ce77192934e5f09e02 SHA-256: a5a09b760d8a7e058a4dea8cb821c70f26072407abbfd532eeaf21baec5612da
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript, which is a common technique for executing malicious code. It also features a link farm pointing to multiple domains, some of which are identified as compromised CMS upload storage, suggesting an attempt to obscure the final destination. The ClamAV detection and ML classifier strongly indicate malicious intent, likely for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

Heuristics 7

  • 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.
  • 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://crewmak.ru/uplcv?utm_term=dragon+ball+streaming+english PDF link annotation
    • http://loscogliodifavignana.it/userfiles/files/mutapolewetiruzubod.pdfIn PDF document text
    • http://claudiodauelsberg.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16139409d2b76e---nobakaxis.pdfIn PDF document text
    • http://carbonelite.ru/file/vajapipu.pdfIn PDF document text
    • http://grafosaleservice.cz/images/fck_editor/file/10828188890.pdfIn PDF document text
    • http://goldenstarhotel.vn/images/uploads/files/pevekitebazijejonaxezoja.pdfIn PDF document text
    • https://nguyenvanhuongloc.vn/app/webroot/files/images/pages/files/41396198610.pdfIn PDF document text
    • https://milorem-service.ru/userfiles/file/tironafatu.pdfIn PDF document text
    • http://mrspk.com/ckfinder/userfiles/files/xiserumevuzejimodaximo.pdfIn PDF document text
    • https://chungangroup.com/uploads/files/202109050316191163.pdfIn PDF document text
    • http://rafaelokazakov.com/file/72116248582.pdfIn PDF document text
    • https://unique.global/wp-content/plugins/super-forms/uploads/php/files/60ae88042a38879437c6a3c7685f195a/gikibuvekimivu.pdfIn PDF document text
    • https://cursosadistanciayonline.com/medios/files/15119323238.pdfIn PDF document text
    • https://keiba-like.biz/js/ckfinder/userfiles/files/1141997582.pdfIn PDF document text
    • http://thefutureofgolf.eu/wp-content/plugins/formcraft/file-upload/server/content/files/16132a4c19fcc6---62528101455.pdfIn PDF document text
    • https://coluer.ir/documents/file/milot.pdfIn PDF document text
    • https://fong-cai.com/upload/files/rosonolezowuw.pdfIn PDF document text
    • http://recko.ru/ckfinder/userfiles/files/gulone.pdfIn PDF document text
    • http://civicwomen.com/ckfiles/files/19063175551.pdfIn PDF document text
    • https://itracmediav5.com/ckfinder/userfiles/files/99608591984.pdfIn PDF document text
    • https://nergizleryapi.com/image/files/25105171551.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_off0000c70b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC70B 10696 bytes
SHA-256: eba3b62b435a0276dce57c316eb43f2ee5ebf2aabbac6517b08a2de9462abd06
font_01_sfnt_off0000df5a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF5A 18596 bytes
SHA-256: 6aed77320cd6dafe5a13d81fc5d431d5728e1ce12dcb4f3bf0c2e9d65bea273d
font_02_sfnt_off000110c4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x110C4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1