Malicious PDF — malware analysis report

Static analysis result for SHA-256 6ef966cd3a779c9a…

MALICIOUS

PDF

79.0 KB Created: 2021-09-04 10:47:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: a307ba49b8f0c2b29fc21c2a7f3fe762 SHA-1: a8f1ce182c492c394daea2a553cd4853a83151a2 SHA-256: 6ef966cd3a779c9ab0d08d68e33142165b771fe85c36e23ec530801350f8f410
116 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The ML classifier strongly indicated maliciousness, and the 'SE_CALLBACK_LURE' heuristic confirms a callback phishing or tech-support scam pattern. The document contains numerous embedded URLs, many pointing to compromised WordPress sites or disposable hosting, suggesting a link farm designed to redirect users. While no scripts were explicitly extracted, the PDF structure and embedded URLs are indicative of a malicious document, likely intended to trick users into initiating a fraudulent phone call.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9949

Heuristics 6

  • 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.
  • Callback phishing phone lure medium SE_CALLBACK_LURE
    Document asks the user to call a phone number in billing, refund, subscription, fraud, or security context — consistent with callback phishing or tech-support scam patterns. Suppressed for legitimate-issuer (IRS/gov/official-form) documents that carry no urgency or charge/dispute escalation.
  • 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://infrive.ru/uplcv?utm_term=groveland+oaks+county+park+pdf PDF link annotation
    • http://austria-ex.com/images/blog//file/fojafasivupijisaragu.pdfIn PDF document text
    • http://www.peplex.it/wp-content/plugins/formcraft/file-upload/server/content/files/1609f3331b65f4---91016493026.pdfIn PDF document text
    • http://cec-intl.ru/app/webroot/files/file/vadojowegir.pdfIn PDF document text
    • https://agenciaboom.com/wp-content/plugins/super-forms/uploads/php/files/6q1onhoe6eq67auqk2euhvsm82/89670536242.pdfIn PDF document text
    • https://phase1acoustics.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a5a3c7ae613---mejivuwalozuv.pdfIn PDF document text
    • https://tidymoney.com/ckfinder/userfiles/files/japugugilipugog.pdfIn PDF document text
    • http://arslanemlak.com/E/file/sejove.pdfIn PDF document text
    • http://akvari-um.ru/userfiles/file/dimilij.pdfIn PDF document text
    • https://stellabakingcompany.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609b2c31de6fc---rinuk.pdfIn PDF document text
    • http://www.juniorcollege.cl/ckfinder/userfiles/files/fenozowezeg.pdfIn PDF document text
    • https://kop-trans.pl/uploads/userfiles/files/devubovasisijigotujev.pdfIn PDF document text
    • http://hutergroup.de/userfiles/file/zofalofimumesosuvilodowo.pdfIn PDF document text
    • http://usa-ex.com/images/blog/file/rajixefos.pdfIn PDF document text
    • https://www.saltriot.com/wp-content/plugins/super-forms/uploads/php/files/3fbef30fc99fb6c6a3a5c58a8aa85018/51282690402.pdfIn PDF document text
    • https://www.elementstraining.co.uk/wp-content/plugins/super-forms/uploads/php/files/76qm5dbge5rct80ls6g5bgbarc/84485480409.pdfIn PDF document text
    • http://www.39koratmachinery.com/file_upload/files/61022034620.pdfIn PDF document text
    • http://elenasteele.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609ef18b4b434---tezelozoboxorapat.pdfIn PDF document text
    • https://jetzterstrecht.hamburg/wp-content/plugins/super-forms/uploads/php/files/6hmoodah89537vfjdka1u1jib7/ruzixarazugizajofa.pdfIn PDF document text
    • https://swotin.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bc4ec42f8bf---45499952515.pdfIn PDF document text
    • http://hevolta.com/upload/file/67020393983.pdfIn PDF document text
    • http://shmountaineering.co.uk/wp-content/plugins/super-forms/uploads/php/files/dm4bj56vp2a2gsfkoeprhighf3/88417558496.pdfIn PDF document text
    • https://bahia-group.com/ckfinder/userfiles/files/27795848418.pdfIn PDF document text
    • https://megatekspb.ru/sites/default/files/uploads/47306899441.pdfIn PDF document text
    • http://braghieriarchitettura.com/userfiles/files/91311072632.pdfIn PDF document text
    • http://morgancountyoh.com/userimages/44269892314.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_off0000cc50.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCC50 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e462.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE462 18608 bytes
SHA-256: 2d7aa7438b72406d404738d05360add14e9bbbebcff840ba25e62316777ee237
font_02_sfnt_off000114aa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x114AA 10932 bytes
SHA-256: dc4c879e25d2d325df906393e2585eacb9695808c56688828b9d71d8086757e8