Malicious PDF — malware analysis report

Static analysis result for SHA-256 b133d0102cde5829…

MALICIOUS

PDF

76.9 KB Created: 2021-09-11 10:26:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: f47db4dc1fd22a11cb22f76dcff35c11 SHA-1: 983fbc867fd4e667822e89115368d44bde290cb8 SHA-256: b133d0102cde5829d4b81f2865b36c59ed230539ea8ded2ead61905405272cb9
66 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs pointing to various domains, suggesting a link farm or redirection strategy. The ML classifier strongly flagged this PDF as malicious, and the presence of multiple external URIs indicates a potential attempt to direct users to harmful content or exploit kits. No scripts were extracted, but the overall structure and heuristic firings point to a malicious document designed for user redirection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

Heuristics 4

  • 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://archism.ru/uplcv?utm_term=brute+force+hack+instagram PDF link annotation
    • http://bbfrontedelmare.com/userfiles/files/repaw.pdfIn PDF document text
    • https://www.hauptsache.cc/wp-content/plugins/formcraft/file-upload/server/content/files/1613144273d26a---bubipatavadafesepo.pdfIn PDF document text
    • http://101eyewear.com/luutru/files/29267901280.pdfIn PDF document text
    • http://singlesync.com/userfiles/file/fasoka.pdfIn PDF document text
    • http://videocycling.info/files/file/94334305097.pdfIn PDF document text
    • https://thietbigas.net/media/files/15168069831.pdfIn PDF document text
    • https://braveathlete.net/geektic/files/47058248995.pdfIn PDF document text
    • http://bwemfjhjk.friend-match.com/upload/files/romol.pdfIn PDF document text
    • https://sunrise-photon.com/upfiles/editor/files/mupiwomamanasisis.pdfIn PDF document text
    • https://birudongker.com/contents/files/23609217797.pdfIn PDF document text
    • http://mkconline.com/landmark/ckfinder/userfiles/files/jeserelasenilexe.pdfIn PDF document text
    • http://jrpst.pl/userfiles/file/fodisebamoz.pdfIn PDF document text
    • http://spellenindex.nl/images/uploads/46162344747.pdfIn PDF document text
    • https://hobbes-group.com/upload/files/maxuvadi.pdfIn PDF document text
    • http://skiflogistics.ru/userfiles/file/kanovatexuwunav.pdfIn PDF document text
    • http://prplus4u.com/ckupload/files/19087795337.pdfIn PDF document text
    • http://remont-etalon.ru/upload/files/80128078418.pdfIn PDF document text
    • http://sarkanyhajo.hu/files/file/22572848595.pdfIn PDF document text
    • http://gerd-pollak.de/userfiles/file/83363153028.pdfIn PDF document text
    • http://studiecarriere.it/uploads/file/nenajamexovubipare.pdfIn PDF document text
    • https://bocion.com/ckfinder/userfiles/files/50920604756.pdfIn PDF document text
    • https://senfina.top/uploads/files/22937310715.pdfIn PDF document text
    • http://sangtaoad.com/uploads/userfiles/file/25402595856.pdfIn PDF document text
    • https://cradlegold.com/wp-content/plugins/super-forms/uploads/php/files/2p4nrtsbvsjkpl9jhkokmhjla3/48037502572.pdfIn PDF document text
    • https://unimedbelem.com.br/painel_template/assets/global/plugins/ckfinder/userfilesfiles/jigesotizipiwisokurag.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_off0000c56f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC56F 10984 bytes
SHA-256: f73b7a482a7f5a90d6c592cc0969b3af7e22aeb280c28d93da6ddca5e0cc5f46
font_01_sfnt_off0000ded3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDED3 17964 bytes
SHA-256: b73a3b29a06b9285bb4d866a66f9bb6cfcfd896fad1ad670e08217d8f1452a7b
font_02_sfnt_off00010d70.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10D70 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1