Malicious PDF — malware analysis report

Static analysis result for SHA-256 48871bf7899646b1…

MALICIOUS

PDF

134.6 KB Created: 2021-07-07 04:55:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-25
MD5: 9cde583084af03a80b534d12fb0db6f2 SHA-1: fe9ab5549657e1be1f4612636611d3ae478116ff SHA-256: 48871bf7899646b13fa6b6d6c9a1ac8373e90940b96f90cab3699785495455b9
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF document that contains numerous links to external websites, many of which are hosted on compromised WordPress sites or disposable domains. The ML classifier strongly indicates maliciousness. The presence of PDF_URI and PDF_SEO_DISPOSABLE_LINK_FARM heuristics, along with the sheer volume of URLs, suggests a link farm or phishing attempt designed to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://crysiq.ru/uplcv?utm_term=tractor+parts+and+their+functions+ppt PDF link annotation
    • https://www.beewellrx.com/wp-content/plugins/super-forms/uploads/php/files/tmp/jopasabe.pdfIn PDF document text
    • https://abril.pe/wp-content/plugins/super-forms/uploads/php/files/a2rpnogvudickn0bjq6gh4aff1/kaxixisowowugu.pdfIn PDF document text
    • http://www.stallionreadymix.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1606cfd554362c---rogibozapegu.pdfIn PDF document text
    • https://wendi101.com/userfiles/file/pedumurozan.pdfIn PDF document text
    • http://xn--80akij1ajew.xn--p1ai/wp-content/plugins/formcraft/file-upload/server/content/files/160b7feb46fbf1---43445501952.pdfIn PDF document text
    • http://www.scmphotography.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160a085a5d77de---sexupuxebevukeb.pdfIn PDF document text
    • https://xn----7sbabak5acz7byau.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/516637559009c98ce3106a8c0e1261b9/tuzozimenosekerisikuto.pdfIn PDF document text
    • http://architettoangeli.it/userfiles/files/mofaxabis.pdfIn PDF document text
    • https://arerp.kr/data/file///wugabekazutof.pdfIn PDF document text
    • https://riondene.ch/img/uploads/file/puvebi.pdfIn PDF document text
    • http://cohn-vossen.com/wp-content/plugins/formcraft/file-upload/server/content/files/160dbaecdc5cc1---fukibonejax.pdfIn PDF document text
    • http://tvtamminhphat.com/uploads/userfiles/file/bokog.pdfIn PDF document text
    • http://groupkaishan.com/d/files/11281067832.pdfIn PDF document text
    • https://www.keystonecare.co.uk/wp-content/plugins/super-forms/uploads/php/files/41a00703983f55bd976b716d95defce1/85520790801.pdfIn PDF document text
    • http://vasilii-orlov.fun/wp-content/plugins/super-forms/uploads/php/files/5ce9c48f59caf21923ca0c2ccbf59525/bulofoxasazetojov.pdfIn PDF document text
    • https://ventana-sur.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607da0e6675e9.pdfIn PDF document text
    • http://czapla-dachy.pl/public/images/fck/file/xegadinidifotugedi.pdfIn PDF document text
    • http://extreamtuning.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160c5356a25d6c---jazojurutibefinadexuli.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_off0001ae85.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1AE85 10732 bytes
SHA-256: 80e83cc3b61a9aefc7ee870697b463b98a0caf732d0c7b8b422ac0bdd7e9a7a4
font_01_sfnt_off0001c71f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1C71F 17516 bytes
SHA-256: 749b3fc1dcf504f544b78652b59610a4cbd3cae1762c3050f65b6f8cdaf812fb
font_02_sfnt_off0001f52c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1F52C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1