Malicious PDF — malware analysis report

Static analysis result for SHA-256 de4c9dac2f964d5b…

MALICIOUS

PDF

75.0 KB Created: 2021-10-11 19:17:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 7f36f9c54882503ae9ae2413641d4296 SHA-1: 44a4e4a529fbda0808aec8e22d7a8e7ed5fd1033 SHA-256: de4c9dac2f964d5b0d360fdfead7a31afb45cd2f38744b4df2dbc607e3848d86
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF was flagged by ML classifiers and ClamAV as malicious, indicating a high likelihood of malicious intent. The heuristics indicate it functions as a link farm, directing users to multiple external URLs, one of which is hosted on a disposable domain. While no scripts were explicitly extracted, the PDF structure and embedded URLs suggest it is designed to redirect users to phishing or malware hosting sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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://xn--fct5g39pjpo.tw/upload/leakstop/files/62569332262.pdf In PDF document text
    • http://bananamusic.tw/uploads/files/202109221343087069.pdfIn PDF document text
    • http://auto4-spb.ru/public/images/ckfinder/files/62740497315.pdfIn PDF document text
    • https://alismobile.co.uk/wp-content/plugins/super-forms/uploads/php/files/094fcd9819cc8a0f9c949020fff477b6/92859897942.pdfIn PDF document text
    • https://giasidaily.com/uploads/userfiles/file/34837828607.pdfIn PDF document text
    • http://satthachkhe.vn/image/file/65598910760.pdfIn PDF document text
    • http://sutinlawkrabi.com/ckfinder/userfiles/files/50493038235.pdfIn PDF document text
    • http://sb-78.ru/files/file/62936885801.pdfIn PDF document text
    • http://intrinhgia.com/admin/webroot/upload/image/files/20412289859.pdfIn PDF document text
    • https://bdblue.com/ckfinder/userfiles/files/49524434896.pdfIn PDF document text
    • http://sprostredkovanieuverov.sk/res/file/kubuvazivuzufozex.pdfIn PDF document text
    • http://vasset.bg/userfiles/file/bubuvavazunuf.pdfIn PDF document text
    • https://xn--interpeas-r6a.es/upload/files/10675930239.pdfIn PDF document text
    • https://nnt52.ru/userfiles/file/zigisovijexigebi.pdfIn PDF document text
    • https://arte-salon.ru/upload_picture/20166185938.pdfIn PDF document text
    • http://www.egavilanes.com/ckfinder/userfiles/files/jobinitofazamosodirogi.pdfIn PDF document text
    • https://wilsonbarrera.com/inicio/wp-content/plugins/formcraft/file-upload/server/content/files/161301d1f769b1---49509920797.pdfIn PDF document text
    • http://xn--80akoseq9f.xn--p1ai/userfiles/file/30482766440.pdfIn PDF document text
    • http://nhactheducthammy.com/upload/files/mevubikelifiketivasa.pdfIn PDF document text
    • https://worldkelo.com/wp-content/plugins/super-forms/uploads/php/files/2083204d680c67042af23ee5f8e37b32/55980415529.pdfIn PDF document text
    • https://aromamarketing.md/img/files/89044893260.pdfIn PDF document text
    • https://ltes.tw-goods.com/UserFiles/files/webopelesovob.pdfIn PDF document text
    • http://hawaiisushi.iorderfoods.com/uploads/files/fosekewaru.pdfIn PDF document text
    • http://feedproxy.google.com/~r/MbOu/~3/896FEnmJZlk/uplcv?utm_term=enjoy+your+drinkPDF 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_off0000c159.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC159 10056 bytes
SHA-256: a382c7db820cff300f21939a1306b720b7b8af321a70c7a6aba39d6460176376
font_01_sfnt_off0000d7aa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD7AA 18236 bytes
SHA-256: eeed681105b3cab0a19560148d44178b416ab7a7d55342d1d46d75be660e1e8d
font_02_sfnt_off00010698.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10698 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1