Malicious PDF — malware analysis report

Static analysis result for SHA-256 a871277acaea97ab…

MALICIOUS

PDF

71.1 KB Created: 2021-06-18 14:00:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-04
MD5: b1fae647f32902e0140d259989e3d7c0 SHA-1: 1530a5100f47d86f555811a766817244a9ca21d5 SHA-256: a871277acaea97abbd0c00d652ccaee962d186f5bd6d88fa267fdedfcb3ff4a2
196 Risk Score

Malware Insights

MITRE ATT&CK
T1059 Command and Scripting Interpreter T1566.001 Spearphishing Attachment

This PDF document was flagged as malicious by ClamAV and an ML classifier. It uses a clipboard-command (paste-and-run) lure. 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 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • Clipboard command execution lure high SE_CLIPBOARD_COMMAND_LURE
    Document tells the user to copy or paste clipboard content into Run, PowerShell, cmd, or another shell-like execution context
  • 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://medok18.ru/wp-content/plugins/super-forms/uploads/php/files/01bbfacec9dcf1dcf45494413bdbceb8/94832267155.pdf In PDF document text
    • http://asesorialuishervas.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d19558d2c0---zapidedapedede.pdfIn PDF document text
    • http://www.ausafrica.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160a6e1544214d---mufedijo.pdfIn PDF document text
    • http://china-hold.com/UploadFile/file/20210530144557372.pdfIn PDF document text
    • https://camile.vn/wp-content/plugins/super-forms/uploads/php/files/4f22uotfh0mbaruu7nbevht5lt/mizirutujegenosider.pdfIn PDF document text
    • http://jyjwqj.com/uploadfile/file/%5C/2021061300573177.pdfIn PDF document text
    • http://mirrorgallery.com/wp-content/plugins/formcraft/file-upload/server/content/files/160801ff024d52---58435792448.pdfIn PDF document text
    • http://broadgatecapital.com/userfiles/file/guxamafijukuxatopunilonar.pdfIn PDF document text
    • http://sazjah.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608e00acced68---41427217169.pdfIn PDF document text
    • http://rauvuonsach.net/images/uploads/files/274999264.pdfIn PDF document text
    • https://soudurelauziere.com/upload/editor/file/27256171296.pdfIn PDF document text
    • https://divorcioconsensual.com.br/wp-content/plugins/super-forms/uploads/php/files/01166167289c32220de4ceb33e069c43/nobelobadelapipunaf.pdfIn PDF document text
    • https://textolinguisticsolutions.com/upload/editor/file/38755853244.pdfIn PDF document text
    • https://www.infratechgroep.nl/wp-content/plugins/super-forms/uploads/php/files/a9a3ad677838a1b06d5f3c42978c8b97/72693657199.pdfIn PDF document text
    • https://topinsolventa.ro/userfiles/file/xeban.pdfIn PDF document text
    • https://k2salight.com/wp-content/plugins/super-forms/uploads/php/files/4396307e8d7bfaa96b9372c37bb3eab2/94489639047.pdfIn PDF document text
    • https://zlatartopalovic.rs//files/97107208969.pdfIn PDF document text
    • https://traveltokiev.com/wp-content/plugins/super-forms/uploads/php/files/p2qm37dhfoq9h8ll4kueuvmnn7/jozojinajamanadeni.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/S30rS-6n6vg/uplcv?utm_term=convert+3+files+into+1+pdfPDF 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d45f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD45F 5008 bytes
SHA-256: a1ae3498c83cd6b85c5534c5738c2ab0b38e9b2508922818da0472610988dc31
font_01_sfnt_off0000e587.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE587 13976 bytes
SHA-256: 57e8712c3c77588def6db898025d0c26e388696d7eb9854cbdb9454ac15b6df6