Malicious PDF — malware analysis report

Static analysis result for SHA-256 e8cb816dd71359da…

MALICIOUS

PDF

80.6 KB Created: 2021-07-06 09:17:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: 76ac9277e74d4ef77800a2660749569f SHA-1: 6f5cbbd4b79c2b7c23051c367c34cd28d95c417b SHA-256: e8cb816dd71359dab1af055040ce0a7be5fc2f901f181879a090c24b80f888aa
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was flagged by multiple heuristics as malicious, including a critical ClamAV detection and an ML classifier. It contains a link farm pointing to numerous distinct hosts, many of which are compromised WordPress upload directories or disposable hosting. The primary purpose appears to be directing users to potentially malicious content or phishing sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9952

Heuristics 6

  • 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.
  • 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://anzmrrn.org/wp-content/plugins/formcraft/file-upload/server/content/files/160b82920d9c8b---93055560147.pdf In PDF document text
    • http://buergerforum-tirol.at/file/sobavopugetufamofimus.pdfIn PDF document text
    • https://unosms.us/userfiles/file/jirobanovizeru.pdfIn PDF document text
    • https://tiklatakip.com/calisma2/files/uploads/notes.pdfIn PDF document text
    • https://advancedbusiness.co/wp-content/plugins/super-forms/uploads/php/files/c700ff96ad1fc9db6c31cb4c4016281c/14566615271.pdfIn PDF document text
    • https://educhina.mn/editor/files/8851895704.pdfIn PDF document text
    • http://albatrossmrn.com/konadnew/userfiles/file/gukeloviweluj.pdfIn PDF document text
    • https://virker-ikke.dk/files/14004097686.pdfIn PDF document text
    • https://www.karavanlakesfet.com/wp-content/plugins/super-forms/uploads/php/files/8e544da5a72f2ab4ec135606e97a97c6/94665395130.pdfIn PDF document text
    • http://coffee33.ru/archive/file/40469786083.pdfIn PDF document text
    • https://www.ideaklinik.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1607216facb03e---fawezonojobutejiwexitax.pdfIn PDF document text
    • http://gingerwooddesign.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a717cab72a1---42132666095.pdfIn PDF document text
    • http://www.whirlpool-beachcomber.at/wp-content/plugins/formcraft/file-upload/server/content/files/1608668c4d5188---68164777109.pdfIn PDF document text
    • http://www.canadiantreasurer.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a0266a34ee3---57694834455.pdfIn PDF document text
    • https://realimpacto.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1607cb22fbfaf2---56008855404.pdfIn PDF document text
    • http://xiangzhuan.tw/upload/files/91019126200.pdfIn PDF document text
    • https://atraba-holding.com/userfiles/file/dalipi.pdfIn PDF document text
    • http://for-rent-aalst.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608864a428e71---wasugujijanaro.pdfIn PDF document text
    • http://grupomarsamo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160935944e6576---27479038851.pdfIn PDF document text
    • http://xn--80aikni6a0b.xn--p1ai/images/file/bowewakimomovufir.pdfIn PDF document text
    • http://playfromhome.org/clients/4/49/49939bf6a151252ba1adfe53d1befa29/File/rotetinorese.pdfIn PDF document text
    • http://www.kammerpop.de/files/file/movikafo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/zMnd8XtcwSM/uplcv?utm_term=water+sort+puzzle+level+136PDF 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000c5dd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC5DD 10660 bytes
SHA-256: bc01a4e1cd863c1143d0aa11de0407d92eb93b3773c92739f0de41f38e91b5d8
font_01_sfnt_off0000de9e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE9E 18820 bytes
SHA-256: fb88c7b492a502d60746a0f4ebce09402b15487a6953c358190d0be428454d88
font_02_sfnt_off00010e7d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10E7D 3564 bytes
SHA-256: ad4df9eb033eaab96f76925e87b0aadf02085f9d85f89cf832b0f06fd5f8dd06
font_03_sfnt_off00011ca6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11CA6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1