Malicious PDF — malware analysis report

Static analysis result for SHA-256 f233b2c57d955f3c…

MALICIOUS

PDF

81.4 KB Created: 2021-06-14 23:19:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-04
MD5: 1070e00ef46c10c39873f0b46d39d8b7 SHA-1: 28e8a9412159c6eeb932a7f0a09b202035d76346 SHA-256: f233b2c57d955f3c3fbf190d13647d624e8a4703f7703186fefc326e21dbd60b
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 0.9998

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://crewmak.ru/uplcv?utm_term=how+to+do+a+heist PDF link annotation
    • https://stagerightstaging.com/wp-content/plugins/super-forms/uploads/php/files/2421f12b5889187ba9c83b03a66c4115/mufofu.pdfIn PDF document text
    • https://dipinkrishna.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606c6ad206239---nudin.pdfIn PDF document text
    • http://www.fsnn.se/wp-content/plugins/formcraft/file-upload/server/content/files/16076fc0f8e06e---metomavugegatisosibenoxuz.pdfIn PDF document text
    • https://noks.cz/wp-content/plugins/formcraft/file-upload/server/content/files/160bad0db2beed---tusorakefeloxokix.pdfIn PDF document text
    • https://www.sacproblemleri.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a6f06724f47---40842244520.pdfIn PDF document text
    • http://www.johnknox.ch/wp-content/plugins/formcraft/file-upload/server/content/files/1608e5a1f1542d---98675477111.pdfIn PDF document text
    • https://3dreamstudios.com/wp-content/plugins/super-forms/uploads/php/files/008d6a098fbda7b0c4a97ffc963e944f/93358333556.pdfIn PDF document text
    • https://yournew.site/wp-content/plugins/super-forms/uploads/php/files/7e6mak56890a0p9l20arrug8kq/99575745328.pdfIn PDF document text
    • http://pmdrecycling.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c500938cdf4---67480204558.pdfIn PDF document text
    • http://www.justgiveahand.org/wp-content/plugins/formcraft/file-upload/server/content/files/1607eb0566b8ea---77082144944.pdfIn PDF document text
    • http://banlinhkienlaptop.com/userfiles/file/nukobivozepisaxi.pdfIn PDF document text
    • http://livestreaming.group/wp-content/plugins/super-forms/uploads/php/files/3u0m8mbqucalb8idlo3cic6qm1i2algp/divinunurozawini.pdfIn PDF document text
    • http://moyamoya.center/images/hand_uploaded/files/kujezifuwawunopalakev.pdfIn PDF document text
    • https://scanclean.bg/upload/ckfinder/files/ramumo.pdfIn PDF document text
    • https://liantoong.com/archive/upload/files/31268026513.pdfIn PDF document text
    • http://mfcwestenkwartier.nl/beta/userfiles/file/17987393411.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_off0001047f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1047F 4836 bytes
SHA-256: 2e1ad894391fd8ebfd8b74f8e479deab1512381575668340c0bc143c4206d0a0
font_01_sfnt_off00011500.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11500 10660 bytes
SHA-256: f8fa950eb39ee3ce2e77df25216494999ddc72517792cf4675f15914bc134559