Malicious PDF — malware analysis report

Static analysis result for SHA-256 816658ab3757554f…

MALICIOUS

PDF

73.2 KB Created: 2021-06-16 11:43:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-02
MD5: 89f60b8072e6611d60de7b48da7712b1 SHA-1: bc389908a310c41b231116ad1336094e02afcaaf SHA-256: 816658ab3757554f75eb56590ac9f0549d1b8efb0d4bf3bcdc1033567c9442f9
156 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://coretry.ru/uplcv?utm_term=4k+followers+apk PDF link annotation
    • https://cutletsmeat.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ab43c662d8d---24708837143.pdfIn PDF document text
    • https://belgradenightlife.info/wp-content/plugins/super-forms/uploads/php/files/fqohnvbod9lpt6fhpdg53abclc/nozujisutuxetejajafe.pdfIn PDF document text
    • http://hattrick-sports.com/wp-content/plugins/formcraft/file-upload/server/content/files/160928da5da5d3---26460193221.pdfIn PDF document text
    • http://alimentosldm.com/userfiles/file/66554082560.pdfIn PDF document text
    • http://alphabodysupplements.com/newerac2c/userfiles/file/87893680992.pdfIn PDF document text
    • https://intelean.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608042b2063a9---76586594643.pdfIn PDF document text
    • http://littlepearlbooks.in/data/eimages/file/72498187750.pdfIn PDF document text
    • https://ewms.vn/wp-content/plugins/super-forms/uploads/php/files/uv4k8prs6iup7mnk6j9s6c6bqt/xovob.pdfIn PDF document text
    • http://architettorobertafasola.eu/userfiles/files/63878930543.pdfIn PDF document text
    • http://batiment-tunisie.com/userfiles/file/revon.pdfIn PDF document text
    • https://xo-sound.ru/userfiles/file/49785700588.pdfIn PDF document text
    • http://www.fsnn.se/wp-content/plugins/formcraft/file-upload/server/content/files/160bc888f98b8e---94388694193.pdfIn PDF document text
    • https://xn----8sbaavnccwq4am.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/664d2dc4df5e03932661acc7192e53e8/letavomud.pdfIn PDF document text
    • https://www.enviedecrire.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ad81a2b803e---fibovopi.pdfIn PDF document text
    • http://orchid-daikanyama.com/userfiles/file/pelanolilibetaberefef.pdfIn PDF document text
    • https://mrmusicfoundation.org/wp-content/plugins/super-forms/uploads/php/files/5fariee95curclf80cl2e9646a/dajonojot.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e26e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE26E 5044 bytes
SHA-256: 062027b0ca025c0aa7e094783f49a6b4fb054f1383af7f52f1a18823c7ab9669
font_01_sfnt_off0000f3c3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF3C3 10672 bytes
SHA-256: 22c4301860982c389b6a05847cd075d01363c26cd4c225e3e30798ab2c20c93e