Malicious PDF — malware analysis report

Static analysis result for SHA-256 4f9e471f13636517…

MALICIOUS

PDF

79.7 KB Created: 2021-06-21 17:49:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-23
MD5: b0323516cb8bedf8dba6b7b19cab0202 SHA-1: d594c3dbb3ae405199e3dc247751d6f95ee5a99a SHA-256: 4f9e471f1363651791515ccc884f669106c50bb92e17be369b80ecfe3c985422
156 Risk Score

Malware Insights

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

The PDF contains multiple embedded URLs, many of which point to compromised WordPress sites hosting other PDF files. The ML classifier and ClamAV detection strongly indicate malicious intent, specifically phishing. The presence of external URI heuristics and link farm indicators suggests the document's primary purpose is to redirect users to potentially malicious external resources.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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 https://cor.org.ar/wp-content/plugins/super-forms/uploads/php/files/e6f5deuj43p3mb3qs562hu4im8/31182263057.pdf In PDF document text
    • http://www.sunargrup.com.tr/wp-content/plugins/super-forms/uploads/php/files/e6rgo4bnap3h81hb6hef91ffr3/31586644748.pdfIn PDF document text
    • http://hi-reid-solutions.com/wp-content/plugins/super-forms/uploads/php/files/515cfba69d7ace1760b412e5ca25a82d/tibob.pdfIn PDF document text
    • http://eko-inwest.eu/upload/file/zefiburuvisoz.pdfIn PDF document text
    • http://wib24-admin.de/uploads/file/19545288465.pdfIn PDF document text
    • http://rittenhousereunion.com/clients/a/ad/ad7d26974070b67854a29702aed78614/File/legiwibudorosuzovuna.pdfIn PDF document text
    • https://husvagnsexpo.se/wp-content/plugins/formcraft/file-upload/server/content/files/1607cdbeb0800e---purinexugevopa.pdfIn PDF document text
    • http://southportrubbish.com/wp-content/plugins/formcraft/file-upload/server/content/files/16077d911ddd46---worolakejorimorevugezized.pdfIn PDF document text
    • https://joyfool.art/wp-content/plugins/super-forms/uploads/php/files/28216a488a6886997e249fc70743220c/zoputaga.pdfIn PDF document text
    • http://lushexperiences.com/wp-content/plugins/formcraft/file-upload/server/content/files/16087153366846---8450189002.pdfIn PDF document text
    • http://www.ncstarim.com.tr/wp-content/plugins/super-forms/uploads/php/files/qabe6gq715m1t39098fln582m1/55056086272.pdfIn PDF document text
    • http://www.unidacardoso.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16074767f8b428---31286074024.pdfIn PDF document text
    • https://autosofortkauf.ch/wp-content/plugins/super-forms/uploads/php/files/57c34v57tsd7paidimihf3up29/99272839843.pdfIn PDF document text
    • https://sandzak.best/wp-content/plugins/super-forms/uploads/php/files/c5c4413f11b19287b2acaf0e110e5bb3/refewate.pdfIn PDF document text
    • http://erex.hu/upload/file/xabazuwefezaki.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/S30rS-6n6vg/uplcv?utm_term=vice+city+hack+codePDF 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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ee60.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE60 4532 bytes
SHA-256: 484acd44098cbec666dff0bc93b29a6386487acd9f1a57f8c1b87482db1d8ab6
font_01_sfnt_off0000fdd4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFDD4 11324 bytes
SHA-256: 3797bbc5dfb6a6eefe1c9b63826e57620a3d0369fde78a77d0cf7e97fa28d4d9
font_02_sfnt_off00012446.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12446 4324 bytes
SHA-256: 05d2457133b820fa77aa358e30e9acfbad3f04c46ced9a37296d9311117db176