Malicious PDF — malware analysis report

Static analysis result for SHA-256 bb7e55508541fcf0…

MALICIOUS

PDF

73.0 KB Created: 2021-09-04 22:56:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-02
MD5: 7c3c1658c7147bcc63d01725573ded98 SHA-1: dd3f74b95d16eaf359487b5f7a1a4b0f6c133947 SHA-256: bb7e55508541fcf0485fd96c78bcffe733dfab4c4ef1310617df844a60a78cac
104 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF document was flagged as malicious by an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories and contains embedded JavaScript. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

Heuristics 6

  • 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 http://antonioruizabogados.es/userfiles/file/sirubujo.pdf In PDF document text
    • https://limsurempat.com/contents//files/polozanoja.pdfIn PDF document text
    • https://www.ayersworthglen.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c8b8fb21d56---ronetujasav.pdfIn PDF document text
    • https://www.vedaaz.com/wp-content/plugins/super-forms/uploads/php/files/fc758cd91e53c78f77e2e42ad02a9409/60257679002.pdfIn PDF document text
    • http://atsrealtyvietnam.com/upload/files/18948077225.pdfIn PDF document text
    • https://zmiz.hr/userfiles/file/xugizuzu.pdfIn PDF document text
    • https://rhagro.com.mx/wp-content/plugins/super-forms/uploads/php/files/d2866dd28258ec29cc0c4c47619d6b7b/478073479.pdfIn PDF document text
    • https://tarsiman.ee/files/file/28016045506.pdfIn PDF document text
    • http://hayatteknoloji.com/webimage/file/lazevutovewifumobetabopuj.pdfIn PDF document text
    • https://sealordhotels.com/ckfinder/userfiles/files/50570436894.pdfIn PDF document text
    • http://www.kzhep.in.ua/wp-content/plugins/super-forms/uploads/php/files/6p6v6fsqj1qfqq5idju32b75c7/17211150469.pdfIn PDF document text
    • http://elosc.com/upFile/file///ITX202108210815539552.pdfIn PDF document text
    • http://1night2day.com/ckupload/files/sazixidu.pdfIn PDF document text
    • https://evocative.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160bdfb75af1b9---6334477936.pdfIn PDF document text
    • https://personalloan2u.com/wp-content/plugins/super-forms/uploads/php/files/123922fa45b336c20b735f7fca15ff46/87317283434.pdfIn PDF document text
    • http://ameshamagazine.com/js/upload/files/wowanuvumi.pdfIn PDF document text
    • http://sosnovgeo.ru/userfiles/file/54401855957.pdfIn PDF document text
    • http://pphjako.pl/userfiles/file/nonobiseva.pdfIn PDF document text
    • https://www.ventisilva.com.br/ckfinder/userfiles/files/78752029416.pdfIn PDF document text
    • http://toyotarent.kr/FileData/ckfinder/files/20210801_BB8A058E72E68C45.pdfIn PDF document text
    • https://sproname.com/files/userfiles/files/nozilin.pdfIn PDF document text
    • http://innotack.com/userfiles/file/gufavozevepimodasolevezu.pdfIn PDF document text
    • http://www.drop-lok.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612cbc156488b---sijemanaso.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3CAf4wW3hvY/uplcv?utm_term=talent+management+pdf+journalPDF 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_off0000bbca.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBBCA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d3e1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD3E1 10772 bytes
SHA-256: f0daab61c143a87cce11915600c3498fae35f94f9c04b4c57cc66391f8b96128
font_02_sfnt_off0000ec6f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC6F 16680 bytes
SHA-256: 7a42357ff47b4d6050167829835c4f456002055e93debd2cabd78dcda31bbb04