Malicious PDF — malware analysis report

Static analysis result for SHA-256 ca6265840b71d261…

MALICIOUS

PDF

70.4 KB Created: 2021-06-13 04:53:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-16
MD5: ba4caf65509dadebe34030ecd27a82c9 SHA-1: c1dd12bdc13b73c36789c945147aed50ef007b76 SHA-256: ca6265840b71d2610f388c733c527375fb15b1c058345cb637f818767ee7db25
96 Risk Score

Malware Insights

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

The PDF file contains numerous external links, many pointing to compromised WordPress sites and disposable hosting, suggesting a link farm for phishing or malware distribution. The ML classifier strongly indicated maliciousness. The document body, though heavily obfuscated, appears to be a lure related to 'basic physics for engineering', likely intended to trick users into clicking the embedded malicious links.

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://infrive.ru/uplcv?utm_term=basic+physics+for+engineering PDF link annotation
    • https://dsodrecital.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a8be5fd6cba---89681302106.pdfIn PDF document text
    • https://pypconsultores.mx/userfiles/file/70462183476.pdfIn PDF document text
    • https://nscs.org/wp-content/plugins/super-forms/uploads/php/files/d8127c66d25023786a4a0c3e8b9170a4/29047671523.pdfIn PDF document text
    • http://aceonlinementors.com/userfiles/file/jirululesawawovatopi.pdfIn PDF document text
    • http://skolicka.eu/foto/images/file/12229545829.pdfIn PDF document text
    • https://ccveg.org/wp-content/plugins/super-forms/uploads/php/files/larj6t6e2gv3qg2dilnqt5prn0/xisore.pdfIn PDF document text
    • https://realwebguys.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c2d9dbd4131---dedegeb.pdfIn PDF document text
    • https://gamletaarnhuset.no/wp-content/plugins/formcraft/file-upload/server/content/files/16085f8bb34083---41920691681.pdfIn PDF document text
    • https://www.siemers-deutschmann.de/wp-content/plugins/super-forms/uploads/php/files/a21rkl9s0tbppl69smqa4ob3jc/98496075688.pdfIn PDF document text
    • https://spectrumohio.com/wp-content/plugins/super-forms/uploads/php/files/ac20b188cd67fc738c27e9f4e34089a6/komekeb.pdfIn PDF document text
    • http://maidnheaven.com/wp-content/plugins/formcraft/file-upload/server/content/files/160758dc8d1639---kabavofilejijakutikivodeb.pdfIn PDF document text
    • https://www.sacproblemleri.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b63dfd76cc3---64449234629.pdfIn PDF document text
    • http://www.eflox.net/wp-content/plugins/formcraft/file-upload/server/content/files/160771daf4af97---fubosil.pdfIn PDF document text
    • http://preserveproperties.com/userfiles/files/lawole.pdfIn PDF document text
    • http://www.lentilles-progressives.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160b7b1e31019d---40010575781.pdfIn PDF document text
    • http://paintingservicesonline.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1609bf5da6a18d---3400520521.pdfIn PDF document text
    • https://www.superioreagle.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607f959c948ae---gejor.pdfIn PDF document text
    • http://allseasonsart.com/uploads/fck_uploads/file/34233769611.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
    • 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_off0000cd47.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCD47 5104 bytes
SHA-256: 043025ae00ff1c5f29e5df0cebee72d4f909c73890f60cda16b153170259be4b
font_01_sfnt_off0000de98.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE98 9376 bytes
SHA-256: 683bee68cc7a8e9a66db34ef6fffb2a9c551e2d6b08708b36e5f42851e179ac7
font_02_sfnt_off0000fea6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFEA6 4324 bytes
SHA-256: 9f355172d696dda274cac500966718f112ce76951f19577ac4888987ea6471b2