Malicious PDF — malware analysis report

Static analysis result for SHA-256 1830cee7e9632aa0…

MALICIOUS

PDF

74.1 KB Created: 2021-07-19 16:22:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: e62c5a49b5e5fdadcc7e2fe5f2c41600 SHA-1: b5a1af623e4a3fa940bf50fe2def5c49f794d4c7 SHA-256: 1830cee7e9632aa0b3d3a77cca3fd78de50c0d3f3e4b61fee1ef5d105efeb0ce
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains a link farm hosted on multiple compromised WordPress sites, indicated by heuristics like 'PDF_SEO_DISPOSABLE_LINK_FARM' and 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM'. The ML classifier also flagged this PDF as malicious with high confidence. While no scripts were extracted, the structure suggests an attempt to lure users to external, potentially malicious, resources.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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.keystonecare.co.uk/wp-content/plugins/super-forms/uploads/php/files/74d6f5a9daddd18b901814de03f750ee/nivojebofok.pdf In PDF document text
    • https://adbetelparaguay.com/wp-content/plugins/super-forms/uploads/php/files/b47c2a9b3016b8c9893ff3c7dc32e5ce/63722157111.pdfIn PDF document text
    • https://cottonweb.net/userfiles/file/71813893467.pdfIn PDF document text
    • https://5of7edwardstreet.com/assets/media/files/lafurasetalalome.pdfIn PDF document text
    • http://alphasigmaoverseas.com/userfiles/file/31325736752.pdfIn PDF document text
    • http://surrattsville69.com/clients/8/81/8122276c22396d7fa0996010cc369f50/File/42511652486.pdfIn PDF document text
    • https://autotrilogy.com/wp-content/plugins/super-forms/uploads/php/files/ea3e73b7ba0d57ebf6124a510da37464/81697788595.pdfIn PDF document text
    • https://www.hamburgeriaagricola.com/wp-content/plugins/super-forms/uploads/php/files/ed92mo2dj5ek5m3ep1knd8ie8c/titunedu.pdfIn PDF document text
    • http://chocolatycakes.com/wp-content/plugins/formcraft/file-upload/server/content/files/160867f4d79be0---wafasojupi.pdfIn PDF document text
    • http://hani-bee.com/userfiles/files/13524679042.pdfIn PDF document text
    • http://global-gypsum.com/wp-content/plugins/formcraft/file-upload/server/content/files/16078dabb65ed6---wegekexekizaxagupinis.pdfIn PDF document text
    • https://tidymoney.com/ckfinder/userfiles/files/6135721674.pdfIn PDF document text
    • https://tramhuonghanoi.vn/upload/files/burij.pdfIn PDF document text
    • http://cetinelektrik.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160aab2cfb58fc---kasusarevefupasibasunu.pdfIn PDF document text
    • http://smartmedicaleg.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609e31e41b163---raxibuvotewufim.pdfIn PDF document text
    • http://deurwater.com/wp-content/plugins/formcraft/file-upload/server/content/files/160732023ea905---zorenezefine.pdfIn PDF document text
    • http://atomleasing.ru/media/File/lamuxatijukaromoxo.pdfIn PDF document text
    • http://muszempilla.com/files/file/86290554962.pdfIn PDF document text
    • https://teenvolunteer.org/wp-content/plugins/super-forms/uploads/php/files/7c1d4add446fd232ed3d8a5b795ee1a4/xujapa.pdfIn PDF document text
    • http://clairerolo.com/userfiles/file/soguwoxudetiwaneg.pdfIn PDF document text
    • https://hopefor.today/wp-content/plugins/super-forms/uploads/php/files/22c65123badb71941c232d03a9254057/supipopukikuv.pdfIn PDF document text
    • http://vipavtoufa.ru/wp-content/plugins/super-forms/uploads/php/files/4aa6d71b0d56521b3dc25f8a9fc099eb/68216028469.pdfIn PDF document text
    • http://nutrisoilvietnam.com/upload/files/dabomusoxanawolezuxume.pdfIn PDF document text
    • http://www.x454.com/wp-content/plugins/super-forms/uploads/php/files/8b6o12kpjjfa5fpq3fpms05ab4/lerixiparales.pdfIn PDF document text
    • https://leunamgroup.com/wp-content/plugins/super-forms/uploads/php/files/0fc30d2b487bd1a118fa4c8ae98cd96c/78839438493.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/Om9ozkHLxGw/uplcv?utm_term=barristers+title+and+escrow+servicesPDF 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_off0000bfd0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBFD0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d7e2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD7E2 16436 bytes
SHA-256: b963fc3a4b7e6d33cf1d4b36f1b51573cf89df133005e1aa736222dee6dae832
font_02_sfnt_off0001028f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1028F 10568 bytes
SHA-256: b8d1ed5e5b32ed1aeeb225035b30147f07c6bc2e5a44862e7a72c242b7bd4197