Malicious PDF — malware analysis report

Static analysis result for SHA-256 806367a9d410c790…

MALICIOUS

PDF

68.7 KB Created: 2021-05-13 10:10:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-12
MD5: fa04679cc7f63ae985ceac5250a2273f SHA-1: cd2521c7683a94777a3cf91f53674bf49e464803 SHA-256: 806367a9d410c790156b2cc0cb39cd80198f79491ba52ea557d871105c0ff7b0
96 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to multiple compromised WordPress sites, which in turn host other PDF files. This suggests a distribution mechanism for malicious content or a phishing lure. The ML classifier strongly indicates maliciousness, and the structure points towards a coordinated effort to host and link to malicious documents.

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://hpx.com.ua/wp-content/plugins/super-forms/uploads/php/files/1ab14d04393e1a39c1c1300e8ccbd3d8/nupilozozulevediwuxaxolug.pdf In PDF document text
    • https://www.cocochan.com.pk/wp-content/plugins/super-forms/uploads/php/files/85100af304b4e410de924db95ffbc128/7098392807.pdfIn PDF document text
    • https://nceptionsolutions.com/wp-content/plugins/super-forms/uploads/php/files/df325737a8533478994091a219964da8/pirun.pdfIn PDF document text
    • http://www.fsnn.se/wp-content/plugins/formcraft/file-upload/server/content/files/16070c6b5ccfbc---tamuxagolanadute.pdfIn PDF document text
    • http://www.platformliften.info/wp-content/plugins/formcraft/file-upload/server/content/files/160756a257e380---fefezujejig.pdfIn PDF document text
    • https://trucraftsmanship.com/wp-content/plugins/formcraft/file-upload/server/content/files/160982b740f592---21741852687.pdfIn PDF document text
    • https://phoenixknights.co.uk/wp-content/plugins/super-forms/uploads/php/files/95fa99a22a1a0af5c1778f84e1baed20/19509715364.pdfIn PDF document text
    • https://ukdirectremovals.com/wp-content/plugins/super-forms/uploads/php/files/4d8b6ee59a3bfd59d3ef283984c03e54/81962215240.pdfIn PDF document text
    • http://irmascaritasdejesus.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/16086c242de387---jogopabapex.pdfIn PDF document text
    • https://www.advids.io/wp-content/plugins/formcraft/file-upload/server/content/files/1609ac9b846ebc---90725411905.pdfIn PDF document text
    • https://artsketch.ru/wp-content/plugins/super-forms/uploads/php/files/e0c3df54a5e380198182e512b9a7a142/worasilumegarosafamixi.pdfIn PDF document text
    • http://www.myhhsi.com/wp-content/plugins/super-forms/uploads/php/files/632fe26589aa25ae27444c5f705cda05/worulutetivum.pdfIn PDF document text
    • http://frederickfollows.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1608731ef752ad---31300895152.pdfIn PDF document text
    • https://www.chauffeur-prive-nice.fr/wp-content/plugins/formcraft/file-upload/server/content/files/16076dbb16df25---49121551426.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/Uplcv/~3/Om9ozkHLxGw/uplcv?utm_term=adobe+illustrator+halloween+poster+templatesPDF 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_off0000d1bf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD1BF 5420 bytes
SHA-256: d09b9b3ab8b822ce1aef395762d8f2349c04a5cd454a89e7937f7d78b5cdcaa6
font_01_sfnt_off0000e40f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE40F 9988 bytes
SHA-256: d8f0084fb7fecb0692f63321ec001c2e1c2890759d243b1f0529d84eacd298a2