Malicious PDF — malware analysis report

Static analysis result for SHA-256 c6fa6b6a08a3a69c…

MALICIOUS

PDF

81.4 KB Created: 2021-10-04 13:44:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 4afa5b9670f73b47604d23967e40a5ef SHA-1: fe2f654c22ea6b64a74edbd2367fd4940fd27268 SHA-256: c6fa6b6a08a3a69cf79675c57a81af8b7a3ae91de7fc1fde4073286e345f2852
96 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised CMS uploads or disposable hosting, indicating a link farm designed to redirect users. The ML classifier strongly flagged this PDF as malicious, supporting the assessment that it is used for malicious redirection. No scripts were extracted, and the document body was unreadable, limiting further analysis of specific lures.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9968

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 http://impressivetravelvietnam.com/upload/files/kijeguweluwapisidorife.pdf In PDF document text
    • http://claudiamelchior.it/images/file/2253475304.pdfIn PDF document text
    • https://sibconsulting.com/contents/files/fijizakowoguxuxiwuzete.pdfIn PDF document text
    • https://henseltech.cz/userfiles/file/zomibibok.pdfIn PDF document text
    • http://nationalcoopadvisors.com/userfiles/files/funerebupikabomiratidanu.pdfIn PDF document text
    • https://satbietthu.com/luutru/files/niwebe.pdfIn PDF document text
    • http://cngwalk.com/fckeditor/userfiles/image/dofoxanipikelemolivixu.pdfIn PDF document text
    • http://webcertain.net/contentupload/fckeditorUploads/organization_/file/vapigiwovumov.pdfIn PDF document text
    • https://alenakovalchuk.ru/wp-content/plugins/super-forms/uploads/php/files/b77355629ea8053eac214e6949542e1d/24628755252.pdfIn PDF document text
    • http://teewer.mn/ckfinder/userfiles/files/mifetedu.pdfIn PDF document text
    • https://promocionesnma.com/wp-content/plugins/super-forms/uploads/php/files/3eae9d5dc693464abada1471db99f440/67164646955.pdfIn PDF document text
    • https://santehsevast.ru/userfiles/files/mewopopepufelotekok.pdfIn PDF document text
    • http://capitolmetrophysicaltherapy.com/userfiles/file/sokifepelup.pdfIn PDF document text
    • https://dezsredstvompx.ru/wp-content/plugins/super-forms/uploads/php/files/ad946d3088e8df0939c0ea4d0ff19efb/zakoxopiwifusivukuzo.pdfIn PDF document text
    • https://securitydm.com/slicice/file/fosuzogako.pdfIn PDF document text
    • https://semut73.com/contents/files/zakituzajune.pdfIn PDF document text
    • http://www.oomewatersport.nl/upload/files/loxojixibufokuse.pdfIn PDF document text
    • https://www.esicm-old.org/admin/lib/ckfinder/userfiles/files/fonaxuboralelabutej.pdfIn PDF document text
    • http://bestapp4u.com/admin/uploadedfiles/file/vanoretegoge.pdfIn PDF document text
    • https://clubelsendero.com/img_pag/file/625040409.pdfIn PDF document text
    • http://maremania.net/img_pagine/file/vaxakiwesumadulotifimifu.pdfIn PDF document text
    • http://jadever.vn/Images_upload/files/41959839478.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=non+communicable+diseases+leading+cause+of+deathPDF 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_off0000d672.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD672 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ee84.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE84 18940 bytes
SHA-256: 936e52aeaaf18d1e8e663d8c8b38d8b8c2dcec0155d64b23cdc6c6e0bada3806
font_02_sfnt_off00011ecb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11ECB 11040 bytes
SHA-256: ecc16b36bdf90b9d0ebfcb9ad75281eaf45bde8b44ad2589270d29764c5cc84f