Malicious PDF — malware analysis report

Static analysis result for SHA-256 1433c79eaf9e662f…

MALICIOUS

PDF

84.7 KB Created: 2021-08-23 12:18:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 3aa7b6a10b2650fe492c9b3b94bf7ecf SHA-1: 6bacda5075a5f8b67d04994473bdd7c366df84e9 SHA-256: 1433c79eaf9e662f9334e6d593783fbfea0e8789d8c13865307f19f12d4b6334
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The ML classifier and ClamAV both strongly indicate maliciousness. The PDF contains numerous links to compromised WordPress sites, suggesting a link farm designed to redirect users to malicious content. The presence of multiple distinct hosts and the use of form-builder plugins for file uploads are common tactics for distributing phishing lures or malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9982

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://www.ddd-iasi.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16078f844d97e3---9349257296.pdf In PDF document text
    • https://www.aironface.com/wp-content/plugins/super-forms/uploads/php/files/4b4ade178578de8de2abc0ac66d0367c/71233884610.pdfIn PDF document text
    • http://www.kissdocs.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160d6f858dbae8---zukapatogexofojav.pdfIn PDF document text
    • http://de-ko-gmbh.com/ckfinder/userfiles/files/98081343300.pdfIn PDF document text
    • http://victorylimo1.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607174a2d5775---zesabaxogijaludezaz.pdfIn PDF document text
    • http://magnumprint.ru/upload/files/subugowezimetutufom.pdfIn PDF document text
    • http://www.specemc.ru/upload/files/nepesetiviwelobamibo.pdfIn PDF document text
    • https://tirthmobile.com/wp-content/plugins/super-forms/uploads/php/files/sh20e3p8unt21uba7cssuf6rsd/75267141710.pdfIn PDF document text
    • https://areshin.ru/wp-content/plugins/super-forms/uploads/php/files/96d48659298087fdd1b467c0fa2c7aa1/nizeripokivufixe.pdfIn PDF document text
    • http://amandamaitland.com/images/file/wazulodojuwi.pdfIn PDF document text
    • http://teplolux72.ru/upload/file/53892044361.pdfIn PDF document text
    • https://benchmarktransitions.com/wp-content/plugins/formcraft/file-upload/server/content/files/160901b3fc33f7---dozega.pdfIn PDF document text
    • https://hocngoaingu123.com/upload/files/xuzuxujatubadegefoke.pdfIn PDF document text
    • http://4bx.pl/public/file/janumisebapuv.pdfIn PDF document text
    • http://mtsskzy.com/userfiles/file/3169844736.pdfIn PDF document text
    • https://jetzterstrecht.hamburg/wp-content/plugins/super-forms/uploads/php/files/hb5739da8eo4r71jpapgufv1k5/21427708726.pdfIn PDF document text
    • http://geombiagioschettino.eu/userfiles/files/75824338283.pdfIn PDF document text
    • https://rodolphe-blanchet.fr/Rodolphe/fckeditor/file/vufogufozewano.pdfIn PDF document text
    • https://blackknowledge.com/wp-content/plugins/super-forms/uploads/php/files/9df73bbc15ad1e7ac595273b048e81af/mojutebomebikegarem.pdfIn PDF document text
    • http://akcjonariusz.com/UserFiles/file/jopuremazos.pdfIn PDF document text
    • https://www.burit.net/wp-content/plugins/formcraft/file-upload/server/content/files/160a9b1a1f206c---sagupebefaxudobufusekamab.pdfIn PDF document text
    • http://dentherapia.hu/files/file/tedaj.pdfIn PDF document text
    • https://linhquan-group.com/upload/ck/files/2403902052.pdfIn PDF document text
    • http://palenice.net/obrazky_clanky/file/midujobiwiwobuwajenisudax.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/S30rS-6n6vg/uplcv?utm_term=happy+birthday+to+you+notationPDF 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_off0000e650.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE650 10488 bytes
SHA-256: aebe08e5d0eaa07cd7072aa47af5e4b93c09ca7971d045eb877a8b8d8c592920
font_01_sfnt_off0000fdc8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFDC8 17264 bytes
SHA-256: ccbdb2099f4c06b31d0243080b00bd7d86c5ca9d8f80e382b73ee92da071c5a2
font_02_sfnt_off00012ab9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12AB9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1