Malicious PDF — malware analysis report

Static analysis result for SHA-256 77f749b3085ed0d7…

MALICIOUS

PDF

68.7 KB Created: 2021-06-24 14:45:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-23
MD5: b257c5f65ba65020ba29db947777b938 SHA-1: 67c41d135cb44aa9441ebff4296d5ca12f69cea1 SHA-256: 77f749b3085ed0d7a90d6270904702a0edb65a992b50bf428117b69b3e15e74a
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

This PDF document was flagged as malicious by 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 5

  • 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 http://www.fattyweng.com.sg/wp-content/plugins/formcraft/file-upload/server/content/files/160a286bc98cbc---mixixarewurapomikoxigopit.pdf In PDF document text
    • https://mn-lawfirm.com/box/userfiles/file/52399176886.pdfIn PDF document text
    • http://studiocalcinoni.com/userfiles/files/50308244965.pdfIn PDF document text
    • https://www.certificagreen.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606e014f9af78---91051987301.pdfIn PDF document text
    • https://www.reflectionuk.com/wp-content/plugins/super-forms/uploads/php/files/5g040itmgf9glk62j0hrpondld/sagev.pdfIn PDF document text
    • https://stallion-international.com/userfiles/file/gomovasusiselajanijetam.pdfIn PDF document text
    • http://www.ashtralmedia.com/wp-content/plugins/formcraft/file-upload/server/content/files/16075369c1ce8a---bibezebonilibifobitatix.pdfIn PDF document text
    • https://floridaholidayplanner.com/wp-content/plugins/super-forms/uploads/php/files/62ca9b1e2f1592b195ceaf473b54ae94/13460245005.pdfIn PDF document text
    • http://for-rent-antwerp.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c10fdcbfa7e---jejogabi.pdfIn PDF document text
    • http://nuyewpilot.academy/wp-content/plugins/super-forms/uploads/php/files/8ebbc387b0449afc037d11c3e88432ff/bolasefaxuzaboze.pdfIn PDF document text
    • https://www.actionconstructionjax.com/wp-content/plugins/super-forms/uploads/php/files/b8a7590759a468062d098b3d4c0a2aa2/wivexofugoxu.pdfIn PDF document text
    • http://woorymart.com/userData/board/file/temiz.pdfIn PDF document text
    • https://atamergranit.com/userfiles/file/mupuwegogifefi.pdfIn PDF document text
    • https://amiablediamonds.com/wp-content/plugins/super-forms/uploads/php/files/46d38016b88ecda9e4d95a81cbcf5e3b/dugapidavixidanodek.pdfIn PDF document text
    • https://na-nule.ru/wp-content/plugins/super-forms/uploads/php/files/ccm3bqt1qkiuvgfuhtg6jaire7/lojisofobanubovezuxupi.pdfIn PDF document text
    • https://alcc.vn/wp-content/plugins/super-forms/uploads/php/files/4kl048q38lv2cbi17p6oeumo1k/kixufapevililalevej.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
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3CAf4wW3hvY/uplcv?utm_term=types+of+chemical+reaction+worksheet+answer+keyPDF 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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000c246.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC246 5252 bytes
SHA-256: e2bd855cfe2e40cd234011811cea37dcb864992026a92c028ba1c1cf83597005
font_01_sfnt_off0000d412.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD412 10336 bytes
SHA-256: 8288027b1074728b7983444ee6428c2cad8dcde69fa265c628f8797ac7e31194
font_02_sfnt_off0000f76c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF76C 4324 bytes
SHA-256: a542ec26cea93e049a2e27cd59b1347dd9bbdea13775fd7b822b3c2b3136116f