Malicious PDF — malware analysis report

Static analysis result for SHA-256 c8505d00576397b1…

MALICIOUS

PDF

74.6 KB Created: 2021-05-10 09:48:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-24
MD5: d784021a05126732d4b268b931756f84 SHA-1: 425ce32cb463c4f455d427402bc28d0abe083870 SHA-256: c8505d00576397b1a0a0b5edd5cda0c04eabf5d0e82350ff22c7f16d15360373
96 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to compromised WordPress sites, suggesting a link farm used for distributing malicious content. The ML classifier strongly indicated maliciousness. Although no scripts were explicitly extracted, the PDF structure and embedded URLs are indicative of a phishing or malware distribution attempt, likely leveraging a spearphishing attachment vector.

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 https://drafthe.ru/uplcv?utm_term=atlantic+slave+trade+worksheet+pdf PDF link annotation
    • http://pansophers.com/wp-content/plugins/formcraft/file-upload/server/content/files/16073f2fe4e17c---22874882061.pdfIn PDF document text
    • http://sinara.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/1609000d670f30---vifidotosuliwaf.pdfIn PDF document text
    • https://craftsmancuttingdies.com/wp-content/plugins/super-forms/uploads/php/files/ddd25520dfd449106da0c825b87d5a51/66723270863.pdfIn PDF document text
    • http://www.northeastmarquees.com/wp-content/plugins/super-forms/uploads/php/files/76f9e11d1b7aded1721c5030757fe007/pawojajasifutamexexope.pdfIn PDF document text
    • https://rockyshairsalon.com/wp-content/plugins/super-forms/uploads/php/files/l97sghjf0smad0e4jgv4e10dqk/noduborexanaxajof.pdfIn PDF document text
    • https://www.duffylighting.com/wp-content/plugins/super-forms/uploads/php/files/6e9636e6c2eb8be62da30e44572a41e4/bipuwux.pdfIn PDF document text
    • http://sciencevier.com/wp-content/plugins/formcraft/file-upload/server/content/files/16086419ecde9d---ritusu.pdfIn PDF document text
    • https://nhaban24h.com.vn/wp-content/plugins/super-forms/uploads/php/files/5ssuinh2e22ldvfmju9lmifgm4/lelevajepoxisizibewurulus.pdfIn PDF document text
    • https://csom.cz/wp-content/plugins/super-forms/uploads/php/files/9bccf0dc450feb6de3d063f67e4d42f9/9600113294.pdfIn PDF document text
    • https://sarujiovalente.com/wp-content/plugins/super-forms/uploads/php/files/ogf0qkto6j9vv83rdimmikmkha/sibekefibir.pdfIn PDF document text
    • https://pluviaterra.mx/wp-content/plugins/super-forms/uploads/php/files/0652b10d653f4b156c7811a8148176b0/selosebolulomeg.pdfIn PDF document text
    • http://www.mtpartnersfl.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607238173cdde---66614027603.pdfIn PDF document text
    • https://alternativecarrepair.com/userfiles/file/sinakalidegujomifo.pdfIn PDF document text
    • http://mijneigenlift.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1607556e8eac8d---51990042932.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
    • 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_off0000d8c5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD8C5 5236 bytes
SHA-256: 448b16ac6c137fb9047dbf74fbd46e6436ca0f06666235785e2121388ce83b7c
font_01_sfnt_off0000ea95.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA95 10332 bytes
SHA-256: f91f421651dc9a4dce00e707ffbc13b0704441610faa68b3e9b082b6f1937f28
font_02_sfnt_off00010dcf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10DCF 4324 bytes
SHA-256: cd94ef65598b1866d0653cdd88243d989fd81359c0e770c2d3a4858f1c2f6d34