Malicious PDF — malware analysis report

Static analysis result for SHA-256 a248b47434412b27…

MALICIOUS

PDF

87.5 KB Created: 2021-05-02 00:21:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-26
MD5: 2c6ee4e9a16bc708c8d4d9de20fbedff SHA-1: 48a8b50492423818276310842140098fcfb9edf2 SHA-256: a248b47434412b279b6a111dd05f22afb7edbfa9b1b922ae04758e35606044ea
156 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier. It contains numerous links pointing to compromised WordPress upload directories, suggesting it is part of a link farm designed to redirect users to malicious content. The document body, though heavily obfuscated, contains references to a 'worksheet', likely a lure to encourage clicks on the embedded malicious URLs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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://www.infranetltd.com/wp-content/plugins/formcraft/file-upload/server/content/files/160727a51105c1---buzalamabunabifirujorekal.pdf In PDF document text
    • https://wscnaturalhealings.com/wp-content/plugins/super-forms/uploads/php/files/cf95500b9752961846cf74821bbc6308/dirisuxekazebov.pdfIn PDF document text
    • http://yuseigachi.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1606f557ca1615---94011687216.pdfIn PDF document text
    • https://petroblend.com/wp-content/plugins/formcraft/file-upload/server/content/files/16088277f37042---jepoliwulutadimaju.pdfIn PDF document text
    • http://la-roofers.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1607a51768b15d---12649172002.pdfIn PDF document text
    • https://glowskincare.net/wp-content/plugins/super-forms/uploads/php/files/b9493f8b8479c9a2317b35a5bb08f305/guledosamakedageroki.pdfIn PDF document text
    • http://halvani.com/wp-content/plugins/formcraft/file-upload/server/content/files/16087fd4baf38d---57858005485.pdfIn PDF document text
    • https://auf.vn/wp-content/plugins/super-forms/uploads/php/files/rejbqnsu1b06lkoq609mqlj4j7/sivuxedifigewizerumiguw.pdfIn PDF document text
    • http://www.nbrownies.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1608742dcf0d12---92545842291.pdfIn PDF document text
    • https://www.audioclinica.pt/wp-content/plugins/super-forms/uploads/php/files/skq4qb67sl6fr9iijouqsmf9c8/74323873937.pdfIn PDF document text
    • http://www.cuadernos.in/wp-content/plugins/formcraft/file-upload/server/content/files/1607831e7d1d2e---34833669323.pdfIn PDF document text
    • https://www.dartmusicfestival.co.uk/wp-content/plugins/super-forms/uploads/php/files/f2ed1b8fc1dd5e1f530153310e67ada6/59633858205.pdfIn PDF document text
    • http://xperion.hu/wp-content/plugins/super-forms/uploads/php/files/2c06f372348d62afe873f3ed9ff52dfc/vanafekokoxapawodix.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/skout/mBVl/~3/LPIa9PGmDLg/uplcv?utm_term=nelson+glycolytic+pathway+worksheetPDF 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
    • 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_off0000f960.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF960 5420 bytes
SHA-256: 6b21af7cb8121521ca0ffb78e9ca553582b4ca3e639ca13ffeb93c126d9a0993
font_01_sfnt_off00010bed.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10BED 13700 bytes
SHA-256: efe72786ed5614bfaf47109b068bda41cce0c873e0e2fb8222b22e7863825bf4
font_02_sfnt_off00013a1c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13A1C 16240 bytes
SHA-256: 538e51fe91aab45a5bb8423cd8bae2855dc51c9f99512ab8ab55b8f3a4a2b409