Malicious PDF — malware analysis report

Static analysis result for SHA-256 6b2458c9959ba09c…

MALICIOUS

PDF

77.8 KB Created: 2021-06-09 00:08:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-11
MD5: ddc600f2a51a533fd4d73c6ba1ad2fe7 SHA-1: 0d5678f5fb79b3c6eb1481d768b3f8fe1ac8dab6 SHA-256: 6b2458c9959ba09c140747cff8baf0bd2aa901a5563a6f3d06071c5764b32051
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links pointing to websites, many of which are hosted on compromised WordPress installations. The 'PDF_SEO_DISPOSABLE_LINK_FARM' heuristic indicates a non-clustered link farm on disposable hosting, suggesting an attempt to manipulate search engine rankings or distribute malicious content. The ML classifier strongly flagged this PDF as malicious, supporting the assessment of a malicious link farm.

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://pixomot.ru/uplcv?utm_term=energy+photosynthesis+and+cellular+respiration+worksheet+answer+key PDF link annotation
    • http://inewbus.com/wp-content/plugins/super-forms/uploads/php/files/nu6p622crpjst5pogjrk5em454/jamimukazazaloraduke.pdfIn PDF document text
    • https://pabausa.org/wp-content/plugins/formcraft/file-upload/server/content/files/160be50ee368f8---gupewej.pdfIn PDF document text
    • https://realestateconnect.pro/wp-content/plugins/super-forms/uploads/php/files/9r5k0hhldhilclpig7dtk2hkc5/kidejogupugoroduvazeki.pdfIn PDF document text
    • https://usssecuritate.ro/userfiles/file/wasexoguruko.pdfIn PDF document text
    • https://www.webplease.it/wp-content/plugins/super-forms/uploads/php/files/bh4pif274a8hjr3s840gsvnmt6/juzoxisufunajox.pdfIn PDF document text
    • https://www.heainc.com/wp-content/plugins/formcraft/file-upload/server/content/files/16072714fee90a---34872274494.pdfIn PDF document text
    • https://nhaban24h.com.vn/wp-content/plugins/super-forms/uploads/php/files/da7ad4g6qeouf8bfjth7mjlbev/remag.pdfIn PDF document text
    • http://yatros.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16098a08005bf7---3701901407.pdfIn PDF document text
    • https://www.hamburgeriaagricola.com/wp-content/plugins/super-forms/uploads/php/files/mtq3na7ll6airt7p52i3p5r5h4/nabokus.pdfIn PDF document text
    • http://willtorock.com/wp-content/plugins/formcraft/file-upload/server/content/files/16099cda1855c7---79764770367.pdfIn PDF document text
    • https://stakeoutllc.com/wp-content/plugins/super-forms/uploads/php/files/233c011cb1a7e23823acfd437fb1c597/zikopabome.pdfIn PDF document text
    • http://www.hollyskauaicondo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bf36a7ea4c3---begeberodurone.pdfIn PDF document text
    • https://akdenizokullari.k12.tr/wp-content/plugins/super-forms/uploads/php/files/93ts4cafa4so2vlk7ugv6kf0ah/buzap.pdfIn PDF document text
    • https://kvgrup.com.ua/wp-content/plugins/formcraft/file-upload/server/content/files/160873870c290d---poferudowegajubavalu.pdfIn PDF document text
    • http://slsnn.ru/content/file/99257692908.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_off0000e416.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE416 5432 bytes
SHA-256: 6348b6f9cfb131bcf1b5a32b2624d6e864d3e1b13427922a40a8463474e363a2
font_01_sfnt_off0000f69a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF69A 10300 bytes
SHA-256: be703ae464ac2aa60b633dc3d4b51f2af05938d5f7da621ff52b4e08a5a8f56d
font_02_sfnt_off000119a2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x119A2 4324 bytes
SHA-256: 9f355172d696dda274cac500966718f112ce76951f19577ac4888987ea6471b2