Malicious PDF — malware analysis report

Static analysis result for SHA-256 e81b78f55d2c9ca2…

MALICIOUS

PDF

307.7 KB Created: 2021-06-23 11:46:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-25
MD5: be418885a9496bd321bc58c48e0a7bfa SHA-1: fa081ee062b7afb96ba332ebfb5d9ae283b63952 SHA-256: e81b78f55d2c9ca240fa7896d7e464ff3236e0fb5fa88ea406215222c558f67b
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous external URIs, many pointing to compromised WordPress sites, suggesting it's designed to redirect users to malicious content or phishing pages. The presence of embedded URLs and the nature of the heuristics strongly suggest this PDF is part of a phishing campaign or a downloader for further malicious payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9729

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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.
  • 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://smidgel.ru/uplcv?utm_term=concepto+de+funcion+matematica+pdf PDF link annotation
    • https://minutesnap.com/wp-content/plugins/super-forms/uploads/php/files/a1524d5bb818663ae1c7bff31d0ecdc1/sokino.pdfIn PDF document text
    • https://mindweave.co.uk/wp-content/plugins/super-forms/uploads/php/files/h4am9a51pt7lq7u4cki0apti9b/67153379727.pdfIn PDF document text
    • https://cutletsmeat.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a37f0e6bfbe---nemowagudod.pdfIn PDF document text
    • http://modelkyujin.com/wp-content/plugins/formcraft/file-upload/server/content/files/16086a4306bc59---daxolakufu.pdfIn PDF document text
    • https://www.birdandwildlifeteam.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ab397fbb1e4---35689835827.pdfIn PDF document text
    • http://analogsys.com/uploaded/file/139125664760ac37bd07556.pdfIn PDF document text
    • https://relleno-acidohialuronico.com/wp-content/plugins/super-forms/uploads/php/files/e3fa340eef65535b3390377d5f72492f/vovejuza.pdfIn PDF document text
    • https://inchirierielicopter.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1608e2a0e0c31f---rezisu.pdfIn PDF document text
    • https://www.hed-endo.hr/wp-content/plugins/formcraft/file-upload/server/content/files/1609b6cf51a0f3---gagejurijudotipuxuk.pdfIn PDF document text
    • http://www.fotografoeventimilano.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608dbf6d0ab69---61235597975.pdfIn PDF document text
    • https://cottonweb.net/userfiles/file/pufexoximuwupipowero.pdfIn PDF document text
    • https://cls-toronto.com/wp-content/plugins/super-forms/uploads/php/files/7a91a71c52c911af7915fd52fa481271/24045488122.pdfIn PDF document text
    • http://www.zav-mito.si/wp-content/plugins/formcraft/file-upload/server/content/files/160a2b9b2e942c---jomebeganobamugeraxofexaj.pdfIn PDF document text
    • http://argra.rs/wp-content/plugins/formcraft/file-upload/server/content/files/16080812718baa---wunasawikabobib.pdfIn PDF document text
    • https://maidintown.co.uk/wp-content/plugins/super-forms/uploads/php/files/36d48b8fc466cb8fcdab800196d3df81/12258102660.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000464b6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x464B6 3024 bytes
SHA-256: 8d8f63b2fb68df1c5f2ea135f00347829fbce7f39c3d0b10a5976a59611a63c8
font_01_sfnt_off00046f82.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x46F82 4900 bytes
SHA-256: 175c3a9f9ac7656aee8046da43d2f3f63a19ddc8d00dd18d546080aca2fdfe58
font_02_sfnt_off00048016.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x48016 15696 bytes
SHA-256: de403672593bc13071eb0f61a295960bd578cad825d01c6edf3cd6adee4b0736
font_03_sfnt_off0004af84.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x4AF84 4324 bytes
SHA-256: 05d2457133b820fa77aa358e30e9acfbad3f04c46ced9a37296d9311117db176