Malicious PDF — malware analysis report

Static analysis result for SHA-256 44d4be7460cb6ee1…

MALICIOUS

PDF

89.8 KB Created: 2021-07-26 06:33:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 8c4db879f396fbe8f53b7325a018e9f9 SHA-1: e77ebec2e025d154eb5797100f529493e29eef51 SHA-256: 44d4be7460cb6ee139e53a1ae0b837803de8c56760f9de2227700afdad254820
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 websites, many of which are WordPress installations. The ML classifier strongly indicates maliciousness. The primary purpose appears to be redirecting users to potentially harmful content through these compromised hosts.

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://augsburger-dartliga.de/uploads/file/30950425550.pdf In PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609688374a59d---47208465388.pdfIn PDF document text
    • http://astmasme.com/userData/board/file/dolojubo.pdfIn PDF document text
    • https://eandjfamilyhealthcenter.com/wp-content/plugins/super-forms/uploads/php/files/8c64e7de445e7b60d8d87a15b0f96520/jopuxamisaralataxo.pdfIn PDF document text
    • http://msci.com.ng/wp-content/plugins/formcraft/file-upload/server/content/files/1608ee92ae0ae4---3572501353.pdfIn PDF document text
    • https://micast.de/wp-content/plugins/super-forms/uploads/php/files/g9ve9fbv5bkfj6cml6vrq8gick/makoxever.pdfIn PDF document text
    • https://ag-concept.ru/wp-content/plugins/super-forms/uploads/php/files/c5306ee1d5613f892c3de8310600cafe/wibisotefafago.pdfIn PDF document text
    • https://clumba-indoor.ru/files/files/14604554326.pdfIn PDF document text
    • http://test.uebersetzungen-nesselberger.de/wp-content/plugins/formcraft/file-upload/server/content/files/1608a1cec5c684---37227915476.pdfIn PDF document text
    • https://nam.it/wp-content/plugins/formcraft/file-upload/server/content/files/16082525130a1a---dowapesupib.pdfIn PDF document text
    • https://ecef-groupe.com/wp-content/plugins/super-forms/uploads/php/files/boatrl4uetlph3kfr0nhisqr94/sukeresemilibesoreri.pdfIn PDF document text
    • http://kesifveotesi.com/files/fugegas.pdfIn PDF document text
    • https://webupdate.ca/wp-content/plugins/super-forms/uploads/php/files/25ro7dgksttrrrf19baic42vlb/tuvobetu.pdfIn PDF document text
    • http://kaufdeinauto.de/wp-content/plugins/formcraft/file-upload/server/content/files/160870797de9fd---miwalo.pdfIn PDF document text
    • https://tahubunting1.com/contents//files/36527798734.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16082358064140---lanuxofuvetuloxisazu.pdfIn PDF document text
    • http://royalgoodviewresort.com/Uploads/file/litorokiduxexilowug.pdfIn PDF document text
    • http://library.nesdb.go.th/ic/admin/ckfinder/userfiles/files/76595021989.pdfIn PDF document text
    • https://givemeit.ru/wp-content/plugins/super-forms/uploads/php/files/93e0da5deb9b21a16ca10f1d0aede000/53933702580.pdfIn PDF document text
    • http://cristal-in.fr/userfiles/file/36137265115.pdfIn PDF document text
    • https://southtours.com/wp-content/plugins/super-forms/uploads/php/files/riijq12miltth6ak90td1osrbr/buvukedujiluzaruwulel.pdfIn PDF document text
    • http://philippinesroadshow.com/wp-content/plugins/super-forms/uploads/php/files/7a1ab025ec3ed3a69ec06eadf7a7ff9d/67240809734.pdfIn PDF document text
    • http://fabrykakonwersji.pl/wp-content/plugins/super-forms/uploads/php/files/4e5a983750c613d8f77c170e1a8585c2/vakonapemojanepatekani.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/YTWXjIUwRh0/uplcv?utm_term=chilobrachys+sp+electric+blue+malePDF 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_off0000f617.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF617 10920 bytes
SHA-256: 6a48b8991093c53167fd1475415bad9a1b96a24b476fa44f9ed0820655c8f41c
font_01_sfnt_off00010f3c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10F3C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001274e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1274E 19172 bytes
SHA-256: f8a5443b8f072e990eb805ffa2834a4aff847521aa95e3a504a06bfc717b0d21