Malicious PDF — malware analysis report

Static analysis result for SHA-256 da3b5cb0981d2b8b…

MALICIOUS

PDF

83.2 KB Created: 2021-06-21 03:41:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-11
MD5: 4886c9051ee771704b990ae18b457391 SHA-1: 1edffa4c6a7b1a78c78c601d6e82bbcc5f9c02ad SHA-256: da3b5cb0981d2b8b9682f7899ba889e1a797a5bdf713d7db9e6d735b66ba4aaa
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The ML classifier strongly indicates this PDF is malicious. It contains numerous links to external resources, many hosted on compromised WordPress sites, suggesting a link farm or redirection mechanism. The document body, though heavily obfuscated, appears to be a lure related to 'drivers interview questions and answers pdf'. No scripts were extracted, but the PDF structure and numerous external links point towards a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 5

  • 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 https://www.bouwenaaneensterkwerkgeversmerk.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1607fc4722b8dd---29226024397.pdf In PDF document text
    • http://mlight.cz/archiv/file/xuzurojizunumikotoju.pdfIn PDF document text
    • https://vernadoc.com/wp-content/plugins/super-forms/uploads/php/files/0750bd9d9dcf79c28a41053bcd3badcd/22893442561.pdfIn PDF document text
    • https://oknoplus-omsk.ru/wp-content/plugins/super-forms/uploads/php/files/a4476fe2814767f247ee5a4624b90cad/rakukazejuna.pdfIn PDF document text
    • https://awlights.com/wp-content/plugins/super-forms/uploads/php/files/74e77a9ad095a4b8219430e609f5ba32/rugusufer.pdfIn PDF document text
    • https://photographerin.agency/wp-content/plugins/super-forms/uploads/php/files/49kcs0blhora7vloqcr6n86oq6/lakofepoxupeda.pdfIn PDF document text
    • https://brandonsmilesdentistry.com/wp-content/plugins/super-forms/uploads/php/files/164vdb3u4r1uunmq25vp01stj3/31261233064.pdfIn PDF document text
    • http://aivieksteslaivas.lv/userfiles/file/wetosonojukakixefobaf.pdfIn PDF document text
    • http://copy2d.com/ftp/image/file/kaluwobodip.pdfIn PDF document text
    • https://ajwatravel.com/wheelmarine/userfiles/file/35159889932.pdfIn PDF document text
    • https://skyfireconsulting.com/wp-content/plugins/super-forms/uploads/php/files/cqns15qttdsjb5ji2dbe7kv8n0/65823167659.pdfIn PDF document text
    • http://kingspec.su/wp-content/plugins/super-forms/uploads/php/files/cp04va5l7b6rd88o6cnko4lug4/mukiwune.pdfIn PDF document text
    • https://jnfarley.com/wp-content/plugins/super-forms/uploads/php/files/q45tl4t48bpbkkcs2jsb58g4k1/46468986280.pdfIn PDF document text
    • https://razvozka24.ru/wp-content/plugins/super-forms/uploads/php/files/79d8ce5fce29b2e85b0cffdce1d69924/neterakipulagobawikoxepiw.pdfIn PDF document text
    • https://www.proctoloji.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607bcdebb89e2---53086645278.pdfIn PDF document text
    • https://kvartira-zalog.ru/wp-content/plugins/super-forms/uploads/php/files/44dae94e97c650e57b2353df1fbdb22f/55859978379.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/LPIa9PGmDLg/uplcv?utm_term=drivers+interview+questions+and+answers+pdfPDF 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00010661.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10661 5280 bytes
SHA-256: 39b7d661a7a735b071a3f3645ff1601ac3a467fa3e4b2e564655d68c0f1acf4d
font_01_sfnt_off0001187e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1187E 11500 bytes
SHA-256: 764ade9e2de1e908a45f320d883c3098d6e47852c9626175ac56d675c4056a81