Malicious PDF — malware analysis report

Static analysis result for SHA-256 471b84be415846f7…

MALICIOUS

PDF

87.5 KB Created: 2021-06-26 06:17:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-22
MD5: 36f91f5cf01a551210e9d303cf6967b7 SHA-1: 94b7d85af2e045c5d04403ff068a1e3e1b1c8ee4 SHA-256: 471b84be415846f73ea79b62131d1ccbeb169b6bf1cc0cf451cd8c1a0b933d75
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file exhibits characteristics of a link farm, with numerous embedded URLs pointing to compromised WordPress sites and other domains. The ML classifier strongly indicated maliciousness, and the heuristic firings suggest a pattern of using link farms on potentially disposable hosting to obscure the ultimate destination. No scripts were extracted from this sample, limiting the analysis of direct execution capabilities.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9835

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 http://bjzjygj.com/fckeditor/editor/filemanager/connectors/php/userfiles/file/xazozirebu.pdf In PDF document text
    • https://heykidsletscook.info/wp-content/plugins/super-forms/uploads/php/files/5984d24f83f8a5b68fb42d8468c0fe30/dikaludomagakejoxi.pdfIn PDF document text
    • http://optikametuje.cz/userfiles/file/kidokidepamaniw.pdfIn PDF document text
    • https://sarujiovalente.com/wp-content/plugins/super-forms/uploads/php/files/9f6e1uiamf3bh6kkkpmedjol5b/82605889672.pdfIn PDF document text
    • https://1sis.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608398bd38519---36849483252.pdfIn PDF document text
    • https://thaiwoodengames.com/files/upload/files/85377979312.pdfIn PDF document text
    • https://rjiminfra.com/wp-content/plugins/super-forms/uploads/php/files/52cf0fa3903bbdc1353a453a4b79f782/vodiworuwabi.pdfIn PDF document text
    • http://mattstergamer.com/wp-content/plugins/super-forms/uploads/php/files/bbmuuvi1k8gpbsikahup9qkbo9/juniwibijubakawi.pdfIn PDF document text
    • http://www.1atlanticfunding.com/wp-content/plugins/formcraft/file-upload/server/content/files/160819c7e848a2---69018656971.pdfIn PDF document text
    • http://andreagarciam.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608fa00fd180d---vusoxodubito.pdfIn PDF document text
    • https://medok18.ru/wp-content/plugins/super-forms/uploads/php/files/f5493156bc3101fd09db1c4217bd1934/gukulabaduwomirexipix.pdfIn PDF document text
    • https://alismobile.co.uk/wp-content/plugins/super-forms/uploads/php/files/5ddfdd17d1ff8af3412259307193d29a/36037479992.pdfIn PDF document text
    • https://ecoinkworld.com/wp-content/plugins/super-forms/uploads/php/files/e2d2519643124d15af86baab53982dcd/buburilak.pdfIn PDF document text
    • http://www.suffaheducation.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a3b3f20930a---39745169605.pdfIn PDF document text
    • http://acetuitioncentre.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160a07e4b377b5---79034959495.pdfIn PDF document text
    • http://shsalumniauditorium.org/clients/f/fa/fa32e32112b7cad64a7d7e78b95ed61b/File/sinex.pdfIn PDF document text
    • https://borderpak.com/wp-content/plugins/super-forms/uploads/php/files/e1313a1c2a98aac9f31ada1aa95e6f55/31633919830.pdfIn PDF document text
    • https://thepetrichortouch.com/wp-content/plugins/super-forms/uploads/php/files/fn3a1rlftk9rnjm6m4nqp9rpto/suxej.pdfIn PDF document text
    • https://senzedigicraft.com/wp-content/plugins/super-forms/uploads/php/files/a668cd478193852b267e2fba9425e76b/xikasokilejaverigo.pdfIn PDF document text
    • http://commsoft.nu/demo/ktb/wsmbilder/files/18085867355.pdfIn PDF document text
    • http://messtores.ca/fck_user_files/file/98415175997.pdfIn PDF document text
    • https://www.rockandroll.blog.br/wp-content/plugins/super-forms/uploads/php/files/a9rb441ga24og8qf7bfh9bt5gd/pojuroba.pdfIn PDF document text
    • http://perfekttorun.pl/pliki/zimunufokesupe.pdfIn PDF document text
    • https://www.businesswatchguardingservices.co.uk/wp-content/plugins/super-forms/uploads/php/files/ooj6c5t4toffll09bkft2b2oqk/44404177909.pdfIn PDF document text
    • https://www.davinci.dk/wp-content/plugins/formcraft/file-upload/server/content/files/1607f4d4d91440---pavoxukura.pdfIn PDF document text
    • http://greenbrier101.com/userimages/95354261603.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1KS0DP0cxss/uplcv?utm_term=whereas+linking+wordsPDF 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_off0000ef5d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF5D 18816 bytes
SHA-256: 4ec64eacd38336cdacdcbdf3c2ec42aaa3e43a46866f2e9f577dba75962e2c60
font_01_sfnt_off00011ecb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11ECB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000136e2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x136E2 10600 bytes
SHA-256: 5ce553cb677cac5ceca3d6d4cc7fdd495204abe588264e7cd1d525557027a67d