Malicious PDF — malware analysis report

Static analysis result for SHA-256 1fb6310ba0f79377…

MALICIOUS

PDF

86.2 KB Created: 2021-09-05 00:14:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: c2784918514cc07a94395a702cb9df75 SHA-1: a16befe03eccee25d5676f8516e25c24b1f99d31 SHA-256: 1fb6310ba0f79377011ff0ddc2a11719f257561220c771a649429b6b29c8cdfe
96 Risk Score

Malware Insights

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

The PDF contains numerous links to external websites, many of which are identified as compromised CMS uploads. These links likely serve as a distribution mechanism for further malicious content. The ML classifier strongly indicates maliciousness, and the presence of link farms on potentially disposable hosting suggests an attempt to obscure the ultimate payload delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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://thepetrichortouch.com/wp-content/plugins/super-forms/uploads/php/files/cgq634g154jki5amgf5rtmfl1a/29735228518.pdf In PDF document text
    • http://projecthouse.bg/uploads/CKfinder/files/37825003638.pdfIn PDF document text
    • http://malbreil.com/userfiles/file/26894531733.pdfIn PDF document text
    • http://artpolyclinic.com/file/files/36313841358.pdfIn PDF document text
    • https://ventana-sur.com/wp-content/plugins/formcraft/file-upload/server/content/files/160e81ec99fdba.pdfIn PDF document text
    • https://grandhotelushba.com/userfiles/file/gexavazabodate.pdfIn PDF document text
    • https://nhadatonline24h.com/Images_upload/files/gabof.pdfIn PDF document text
    • http://micruts.org/userfiles/file/misigipijexib.pdfIn PDF document text
    • http://www.viksexteriors.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a33ccc0e3f8---50329697111.pdfIn PDF document text
    • https://naseeha.org/wp-content/plugins/super-forms/uploads/php/files/ca84804653e63151f56cd12b4cdbc8ab/24580816158.pdfIn PDF document text
    • http://daiduongmetal.com/uploads/ckfinder/files/19282443600.pdfIn PDF document text
    • http://dansungsala.com/uploads/files/lawakumuninewelesedaleg.pdfIn PDF document text
    • https://licorne-hotel-restaurant.com/userfiles/file/41425647882.pdfIn PDF document text
    • http://mylodge-naoshima.com/tiromidakodozularimoda.pdfIn PDF document text
    • http://www.libroparlatolions.it/backoffice/ckfinder/userfiles/files/46987602781.pdfIn PDF document text
    • http://www.putnamtaxi.net/wp-content/plugins/formcraft/file-upload/server/content/files/160d84fb763926---76377497047.pdfIn PDF document text
    • https://www.cr-sdc.org/wp-content/plugins/super-forms/uploads/php/files/4077ba860606ce7b02f78ac85452a621/sevedefujowetuteli.pdfIn PDF document text
    • http://exmar.it/foto_fck/file/reduve.pdfIn PDF document text
    • http://www.primalegal.eu/wp-content/plugins/super-forms/uploads/php/files/1vt0h7rnvctr3fi1jh2akag3v6/revamig.pdfIn PDF document text
    • http://abogarestudio.com/userfiles/file/26754066705.pdfIn PDF document text
    • https://arch.ua/ckfinder/userfiles/files/rorovube.pdfIn PDF document text
    • https://www.chauffeur-prive-nice.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160f7c675c3823---juposofijijowob.pdfIn PDF document text
    • http://ms-krmelin.cz/app/webroot/files/files/letabosu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/FevRqgeaUVY/uplcv?utm_term=relative+defining+clauses+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://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e58f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE58F 10784 bytes
SHA-256: 56b20c48000918c590645e0c0eac52dcba195f3d0150beb841008a6a6e318eaa
font_01_sfnt_off0000fe57.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE57 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011669.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11669 20592 bytes
SHA-256: 08df0d76e874afe382ce9e6ae809159b304e5437b29ddb832e05ed226b9c00fc