Malicious PDF — malware analysis report

Static analysis result for SHA-256 816469e6b8f4c210…

MALICIOUS

PDF

94.8 KB Created: 2021-06-19 01:09:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-25
MD5: bccb90c075934a829ec3c2252b9c161f SHA-1: 8dbbf1f60166dc21e40b295660c159f0938eeb46 SHA-256: 816469e6b8f4c210efa7f40dbb41fae5d99cb783413995c4afb8cba5d583a3ab
96 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to multiple distinct hosts, many of which appear to be compromised CMS upload directories. The ML classifier strongly indicated maliciousness, and the structure suggests an attempt to lure users to external sites. No scripts were extracted, but the PDF's nature as a link farm is a common tactic for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9995

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://triumphtoday.org/wp-content/plugins/formcraft/file-upload/server/content/files/160b7dc5ada94f---terufipowewodukuz.pdf In PDF document text
    • http://www.skupp.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1606f2b90d6b47---85949847214.pdfIn PDF document text
    • http://stevis.cz/files/file/tabesuzililodozepu.pdfIn PDF document text
    • http://cohn-vossen.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c50682672ac---metovorozikug.pdfIn PDF document text
    • https://kodeac.com/wp-content/plugins/super-forms/uploads/php/files/k6fsnvad4vrtufi09pcsu4sa3s/98709185626.pdfIn PDF document text
    • https://livingcircles.ch/wp-content/plugins/formcraft/file-upload/server/content/files/1606cffdd2513d---pevagunopipi.pdfIn PDF document text
    • http://xn----8sbpvg0afdbe.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/d7b5rlr4k5tchmq07rtvu23au3/53435640331.pdfIn PDF document text
    • https://retentionstudentexperience.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a36968849e6---nejetotegatanufidixew.pdfIn PDF document text
    • http://ottotech.center/userfiles/file/muwulesoni.pdfIn PDF document text
    • http://malbreil.com/userfiles/file/toxuzutowikojaziwad.pdfIn PDF document text
    • https://www.dentaltaxpros.com/wp-content/plugins/super-forms/uploads/php/files/1c02b11117c80b8680b876cac4b52794/24802750886.pdfIn PDF document text
    • http://diagonal.org.ar/wp-content/plugins/formcraft/file-upload/server/content/files/1606c96a9a528f---22983015399.pdfIn PDF document text
    • http://deurenhanger.nl/userfiles/file/kizofironawimarukiwu.pdfIn PDF document text
    • https://wrd13.com/force/file/tujodow.pdfIn PDF document text
    • http://www.myhhsi.com/wp-content/plugins/super-forms/uploads/php/files/b3cf9fa453bc5c7f0b6b299549da58e1/89932681908.pdfIn PDF document text
    • https://canadianrelocation.net/wp-content/plugins/formcraft/file-upload/server/content/files/160900c8c209bb---zatatevemonal.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/Uplcv/~3/FevRqgeaUVY/uplcv?utm_term=buku+antonio+gramsci+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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00012705.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12705 5320 bytes
SHA-256: 99a7640774984d287e63f167bc5b0f6d40893443e5f51b7f7fdca559702f984f
font_01_sfnt_off00013905.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13905 11376 bytes
SHA-256: eb1f194bd8575c5be539f1b6c8d6f34fa40e60b5919252fc618027378949c2a1
font_02_sfnt_off00015f4f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15F4F 4324 bytes
SHA-256: cd94ef65598b1866d0653cdd88243d989fd81359c0e770c2d3a4858f1c2f6d34