Malicious PDF — malware analysis report

Static analysis result for SHA-256 6d90350fd54b1051…

MALICIOUS

PDF

77.0 KB Created: 2021-06-18 18:48:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-11
MD5: d5bddaa6fd5c367344ad94355e227550 SHA-1: 433285b1caf590964bf2a699478303ba522d2f9b SHA-256: 6d90350fd54b1051fd3ef73fb79b0f3bbd05f62e6f3d0e0f924eb99284524c70
96 Risk Score

Malware Insights

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

The PDF contains numerous external links, many pointing to compromised WordPress sites, suggesting a link farm or SEO poisoning tactic. The ML classifier strongly indicated maliciousness. While no scripts were explicitly extracted, the PDF structure and numerous URLs suggest it's designed to redirect users to potentially malicious content or phishing sites.

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://catamma.ru/uplcv?utm_term=multiplication+and+division+of+fractions+pdf PDF link annotation
    • https://www.cdscabling.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160a3223acdb73---vuratokelolasifolebe.pdfIn PDF document text
    • https://chpcentre.com/files/file/doxesejibokapirugala.pdfIn PDF document text
    • https://primax.fr/wp-content/plugins/super-forms/uploads/php/files/76rkbcitmi77ge69d4mr6aebu4/wolilopifikesimoma.pdfIn PDF document text
    • http://tuzvedo.hu/elemek/file/39078766869.pdfIn PDF document text
    • http://brmhn.com/userfiles/file/20210518232315_a4s8z5.pdfIn PDF document text
    • https://awlights.com/wp-content/plugins/super-forms/uploads/php/files/e5d0bb4f3632f8c1c00320622341a25b/63696555925.pdfIn PDF document text
    • https://kodeac.com/wp-content/plugins/super-forms/uploads/php/files/sau5h8d5obuktjvmjilm4e2hrs/46515794339.pdfIn PDF document text
    • https://dienlanhhonganh.com/images/pic/file/28923308652.pdfIn PDF document text
    • http://vizit-k.net/uploads/editor/files/88049839533.pdfIn PDF document text
    • http://theopenhouseclub.com/wp-content/plugins/super-forms/uploads/php/files/c78a266e8ba00a1a1cbdbbd34450e6bf/33019405057.pdfIn PDF document text
    • https://wills.sg/wp-content/plugins/super-forms/uploads/php/files/8d2163cde2a7cf19179dbbaf9542e219/naxosopuriwega.pdfIn PDF document text
    • https://calmoinc.com/upload/editor/file/2228978622.pdfIn PDF document text
    • https://asiatravel.kg/wp-content/plugins/super-forms/uploads/php/files/47fc1eabda6650c7eeafada6f02a4cc2/63275774123.pdfIn PDF document text
    • https://www.d-table.com/wp-content/plugins/super-forms/uploads/php/files/9ecd5be428099456347e7eeb024fdc7f/suzenu.pdfIn PDF document text
    • http://duszek-lasu.pl/userfiles/file/femukunebotoza.pdfIn PDF document text
    • https://coloreverything.love/wp-content/plugins/super-forms/uploads/php/files/592db9526769c76ae1ba26c9d7fa8639/13472318601.pdfIn PDF document text
    • http://www.shipsupply.co.mz/wp-content/plugins/formcraft/file-upload/server/content/files/1608d01485f3ad---nenefagewozetewagavojole.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ed3b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED3B 5212 bytes
SHA-256: 731d3db0b474dbb6d70297097dd38f4297d21429e267fe04773abaf635e275fc
font_01_sfnt_off0000ff1a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFF1A 11724 bytes
SHA-256: 0e9be1516dde1d440d1b02996e779546c8a565ac6a913e24a14811f5ad258494