Malicious PDF — malware analysis report

Static analysis result for SHA-256 8d7f4e2e859b6543…

MALICIOUS

PDF

78.4 KB Created: 2021-07-19 15:01:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 7fbffb56d11e7bb6211bb73a153dc10f SHA-1: a26aa29891b78bc4b92649406479ace03ec9c8d4 SHA-256: 8d7f4e2e859b6543387fc5db7f3128efcd8695f8bf029f86c464232e3f5ea464
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file contains a link farm pointing to numerous compromised WordPress sites, indicating a likely attempt to redirect users to malicious content. The ML classifier strongly flagged this PDF as malicious, supporting the assessment of a malicious link farm. No scripts were extracted, and the document body was unreadable binary data.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9949

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.alertgy.com/wp-content/plugins/super-forms/uploads/php/files/4ef5017d62d481ea2ee1246384c6c466/79916451369.pdf In PDF document text
    • https://alcc.vn/wp-content/plugins/super-forms/uploads/php/files/t1tvr0pu5alfv0nblsok0d34ll/zubirukujudulezomewes.pdfIn PDF document text
    • https://controlcert.se/wp-content/plugins/formcraft/file-upload/server/content/files/160d37386ac4d4---34449771595.pdfIn PDF document text
    • https://www.alpha-dynamics.gr/wp-content/plugins/formcraft/file-upload/server/content/files/160be18a9a3be8---gomuzozidawavelafi.pdfIn PDF document text
    • https://www.kasekimi.com/wp-content/plugins/formcraft/file-upload/server/content/files/16073e555a8854---75044957103.pdfIn PDF document text
    • http://pattonbrayboy.com/clients/8/84/8444fd18e659e4cf0f5d78ff5dcadce3/File/xurikiba.pdfIn PDF document text
    • http://vijyaiprismcrm.com/userfiles/files/25394991512.pdfIn PDF document text
    • https://yingzhaoliuart.com/upload/file/44645187731.pdfIn PDF document text
    • https://www.reliancecareuk.com/wp-content/plugins/super-forms/uploads/php/files/dc28c1f43925bee1e79f619c5e1341bf/fipulaso.pdfIn PDF document text
    • https://unique.global/wp-content/plugins/super-forms/uploads/php/files/92076595862889174c46798e69b3cd86/16901657631.pdfIn PDF document text
    • https://makemycake.gr/wp-content/plugins/super-forms/uploads/php/files/hmos5pou5di5gsummu9hg1it3g/vifojok.pdfIn PDF document text
    • http://www.etoiles-recrutement.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d65af1df0b1---72634731643.pdfIn PDF document text
    • https://www.paparazzirestaurant.com.au/wp-content/plugins/super-forms/uploads/php/files/20c27baad72e44b0e6462c3101cea513/fedib.pdfIn PDF document text
    • http://www.benvenutialmare.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f015cbd28d8---zutakobuwog.pdfIn PDF document text
    • http://119hero.kr/userData/board/file/85705565146.pdfIn PDF document text
    • https://plumcourse.com/wp-content/plugins/super-forms/uploads/php/files/b52ebd504206bd9303d68654c454b88f/5495472698.pdfIn PDF document text
    • https://rjiminfra.com/wp-content/plugins/super-forms/uploads/php/files/7fc21da0e3dbf26502805003808429f5/7502907415.pdfIn PDF document text
    • http://mofrantech.com/userfiles/file/wolubujid.pdfIn PDF document text
    • http://cedresarquitectura.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d15f476996---nenijuwenozukelupunegezaw.pdfIn PDF document text
    • https://londonvipchauffeur.co.uk/wp-content/plugins/super-forms/uploads/php/files/f8087d4342dd85557255f202fd3ff079/84075540891.pdfIn PDF document text
    • http://instant-image.net/UserFiles/Site/File/zasekefarosiwulukalas.pdfIn PDF document text
    • https://jin-ji.com/upload/files/84567158051.pdfIn PDF document text
    • http://antifftech.com/uploadfile/file///2021051020465988.pdfIn PDF document text
    • https://gulertrafik.com/wp-content/plugins/super-forms/uploads/php/files/6qffc2n3h381r2jj9caki5kh4l/golezuvigopawoxata.pdfIn PDF document text
    • http://cropscipublisher.com/files/upfiles/file/tobuxiwugeboti.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BvfzZFkJO3s/uplcv?utm_term=wait+for+me+to+come+home+ed+sheeranPDF 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_off0000d004.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD004 15864 bytes
SHA-256: 9c7919f77d267dbb5da2c9a6b1a2bf8bdd5bb2029677c29bda026b543301c3e7
font_01_sfnt_off0000f907.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF907 10688 bytes
SHA-256: 23f4a94eb046d61d8c69851fc9813f72d1d56c4d1783355166f417ae80efb31a
font_02_sfnt_off0001116c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1116C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1