Malicious PDF — malware analysis report

Static analysis result for SHA-256 df51e08cd0d686ef…

MALICIOUS

PDF

124.2 KB Created: 2021-08-31 22:24:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: da337b790c0895ef4a3ba673f2c950d2 SHA-1: ddcc294a39d4e0b75bfcee979beb74c46eba4aa0 SHA-256: df51e08cd0d686efc94c234633959bce5301ac9c3d3790884dc3ad9981b46f6b
96 Risk Score

Malware Insights

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

The PDF file contains a link farm with numerous external URLs, many pointing to compromised WordPress sites. The ML classifier strongly indicated maliciousness, and the structure suggests an attempt to manipulate search engine rankings or distribute further payloads. No scripts were extracted, but the embedded URLs are the primary indicators of malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9979

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://scapetime.net/images/website/user/files/lamubegosofi.pdf In PDF document text
    • http://sivam.pl/files/file/tofepak.pdfIn PDF document text
    • https://nuevocoach.co.uk/wp-content/plugins/super-forms/uploads/php/files/b183bd6d6d52cf57a2abeb782391c97e/xozaxexalowige.pdfIn PDF document text
    • https://gfow.om/wp-content/plugins/super-forms/uploads/php/files/tvsep7j5l1kqdlrlrhebv3su69/43403826840.pdfIn PDF document text
    • http://learnersdigest.org/userfiles/file/pabukukomoxekipaxufamadij.pdfIn PDF document text
    • http://poketomecam.com/uploads/files/bumupoxuxaxivobozitave.pdfIn PDF document text
    • http://szzxwx.com/Upload/Upload/file/202172419541690.pdfIn PDF document text
    • http://dabbleanddesign.com/clients/c/c6/c60e280709801842a26e47e23f21f170/File/31926016790.pdfIn PDF document text
    • https://www.potterycommercials.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1609e00081f0d1---63469611237.pdfIn PDF document text
    • https://bizdrive.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1/160784c021a46a---53459276163.pdfIn PDF document text
    • https://soechi.net/userfiles/file/80904570385.pdfIn PDF document text
    • http://fullcolorspandoeken.nl/userfiles/file/karidulobutesiwife.pdfIn PDF document text
    • http://volkshilfe-vlbg.at/images/content/files/tuninizi.pdfIn PDF document text
    • http://usatovl.ru/upload/fckeditorfile/33251187753.pdfIn PDF document text
    • http://mikomisushiwc.com/uploads/files/vufirujorodizon.pdfIn PDF document text
    • http://tfforming.ru/d/files/senujikodaxukagopufeb.pdfIn PDF document text
    • http://cbstav.cz/file/suxozutasadigimul.pdfIn PDF document text
    • https://qamarapps.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612803a8e35f1---1759687485.pdfIn PDF document text
    • http://duszek-lasu.pl/userfiles/file/soruziwudoragubawiv.pdfIn PDF document text
    • http://montaze.org/democms/userfiles/file/wunevesogegut.pdfIn PDF document text
    • http://kapsalonvogue.nl/files/file/59838154590.pdfIn PDF document text
    • http://permanentnimakeup-brno.cz/userfiles/files/fomebaruxe.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/Om9ozkHLxGw/uplcv?utm_term=they+love+the+darkness+biblePDF link annotation
    • http://kioskcondoweb.wpengine.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b62565aaa98---migisixulejafonof.pdfIn 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://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_off00017703.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x17703 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00018f1a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x18F1A 10720 bytes
SHA-256: 0ef924517a7485e22d4b0af616eea23278fb817827c9ee993f2a12211f5b41bc
font_02_sfnt_off0001a7b6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1A7B6 22928 bytes
SHA-256: cdb908f7f8de784c21ef7d2c06538df8b33f63cab1b7b44b78f5468a7cac8e3f