Malicious PDF — malware analysis report

Static analysis result for SHA-256 fbb7da4875399e86…

MALICIOUS

PDF

89.0 KB Created: 2021-09-02 14:54:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: e8f51ec0030bf094028dafe034b6e191 SHA-1: 481a0e23be45ae5cd08dc0570b12094105062ec2 SHA-256: fbb7da4875399e862aecf44eef95c8613083ba861b8d1568f299889a61dcbeae
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a large number of links pointing to compromised websites, many of which are hosted on disposable domains or WordPress upload directories. The heuristic 'ML_NYX_PDF_MALICIOUS' strongly indicates malicious intent, and the presence of embedded URLs suggests an attempt to redirect the user to malicious content. No scripts were extracted from this sample, but the link farm pattern is a common technique for distributing malware or phishing lures.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9982

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://smidgel.ru/uplcv?utm_term=medical+billing+training+manual+pdf PDF link annotation
    • http://chiengthai.com/file_media/file_image/file/lurux.pdfIn PDF document text
    • http://954move.com/clients/4890/File/46697182605.pdfIn PDF document text
    • https://tusenfotingen.nu/anvandarbilder/108/files/bagiwulululitapelabi.pdfIn PDF document text
    • http://azs-szermierka.pl/zdjecia/fck/file/vozivilexaje.pdfIn PDF document text
    • https://monarchwinemerchants.com/wp-content/plugins/super-forms/uploads/php/files/6a3f600fa71e726c0d2b9068e4a94a61/87979956212.pdfIn PDF document text
    • https://yournew.site/wp-content/plugins/super-forms/uploads/php/files/4di1r939cg80ljg32cdsets5nn/zevurorigos.pdfIn PDF document text
    • http://kingsfinancialconsulting.com/userfiles/file/76018147900.pdfIn PDF document text
    • http://caacoding.net/wp-content/plugins/formcraft/file-upload/server/content/files/160802f52ba76f---dipukawokolamav.pdfIn PDF document text
    • http://www.ellisrasbetonwerke.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160b806202131e---20697274985.pdfIn PDF document text
    • http://servis-hradec.cz/files/file/19149785918.pdfIn PDF document text
    • http://biblioteka-belzec.pl/upload/files/pufojoterujunu.pdfIn PDF document text
    • https://frasertechno.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a866134366c---9364580028.pdfIn PDF document text
    • https://hoalavender.net/upload/files/1588292545.pdfIn PDF document text
    • https://www.ayersworthglen.com/wp-content/plugins/formcraft/file-upload/server/content/files/16072cd5c6911b---nedanof.pdfIn PDF document text
    • http://www.akutrans.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ad767013835---62436231858.pdfIn PDF document text
    • http://ontis.sk/editor_uploads/system/files/10263553526.pdfIn PDF document text
    • https://www.dazzlingdecor.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160888b5787d25---18172878706.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/161294c3353e1c---sewizopijob.pdfIn PDF document text
    • http://tuhocxuatnhapkhau.com/uploads/ckfinder/files/ramomalunuzosuwe.pdfIn PDF document text
    • http://tuanlongland.com/upload/files/samovivazewamowegi.pdfIn PDF document text
    • https://charterboatdeliverance.com/uploads/files/butafapogapojerenu.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_off0000f708.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF708 17680 bytes
SHA-256: f33e4dd9101d19179e5d84a358cd7863ea7c42f72ba05ebb2ff7c62d58cf004d
font_01_sfnt_off00012563.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12563 10908 bytes
SHA-256: b1c5beeba6b7c9e0fc9facc450cd5161aa0494c768c181eec92dff1b8fa0d2ff
font_02_sfnt_off00013e21.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13E21 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1