Malicious PDF — malware analysis report

Static analysis result for SHA-256 331d555d99e89e1f…

MALICIOUS

PDF

88.6 KB Created: 2021-08-23 09:18:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 1b00f59c1a7639f7f94c072d057b1805 SHA-1: 7a0654c8f0b57812cf44e85f3837da37f61b9377 SHA-256: 331d555d99e89e1fdf92812facef16aee4cf915a3015db609f3b78908f877665
156 Risk Score

Malware Insights

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

The PDF document contains a large number of links pointing to various domains, many of which are associated with compromised CMS uploads or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The document body is unreadable, but the heuristic firings clearly show a link farm designed to redirect users to potentially harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://mxagproducts.com/upload/browse/file/14974759820.pdf In PDF document text
    • http://ck-tct.ru/userfiles/file/limamirekone.pdfIn PDF document text
    • http://3duct.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609b7ec51aa0e---77362875181.pdfIn PDF document text
    • https://ethiquedevelopers.com/wp-content/plugins/super-forms/uploads/php/files/c4f38a4c3bf9f9e7ec6a937f27710fcf/48618566406.pdfIn PDF document text
    • https://www.hotel-palladium.gr/wp-content/plugins/super-forms/uploads/php/files/mlc4tptqa2ueesvh8np9iv4jop/38022561832.pdfIn PDF document text
    • http://www.itbaloch.com/wp-content/plugins/formcraft/file-upload/server/content/files/160849341924a0---7036405178.pdfIn PDF document text
    • https://xyoaa.org/sites/default/files/files/99264173716.pdfIn PDF document text
    • http://mattstergamer.com/wp-content/plugins/super-forms/uploads/php/files/f6h6jm26vv2s6u5klrds83pd44/24198477402.pdfIn PDF document text
    • http://movediary.com/userfiles/file/josisokelobujotumizaroxe.pdfIn PDF document text
    • https://www.hemoroidklinigi.com/wp-content/plugins/formcraft/file-upload/server/content/files/16075eebdeb4b9---najigugudozixib.pdfIn PDF document text
    • https://asthasupermarket.com/userfiles/file/69163339085.pdfIn PDF document text
    • https://xlux.vn/wp-content/plugins/super-forms/uploads/php/files/83baq8bi7u2s1qvqnauns2l7ql/deboravura.pdfIn PDF document text
    • http://rethabise.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/16077a01bd8f08---9751130816.pdfIn PDF document text
    • http://ats-dz.com/userfiles/file/pafeworafaxomoso.pdfIn PDF document text
    • https://jagominum.com/contents/files/salex.pdfIn PDF document text
    • http://aliancegroup.su/wp-content/plugins/formcraft/file-upload/server/content/files/160dbc465020a4---ximosa.pdfIn PDF document text
    • https://www.gasserbush.com/wp-content/plugins/super-forms/uploads/php/files/3f12f64e5b84ebdcc76a6ace20f145af/winobinetagixizase.pdfIn PDF document text
    • http://sosnovgeo.ru/userfiles/file/misujoji.pdfIn PDF document text
    • http://hi-techfiber.com/userfiles/file/42282734508.pdfIn PDF document text
    • http://mamam.by/upload/File/file/dabinaralixivojowemeb.pdfIn PDF document text
    • https://songhong.info/userfiles/file/44258049369.pdfIn PDF document text
    • http://savoie-outils-coupants.com/ckfinder/userfiles/files/wibuwutoj.pdfIn PDF document text
    • http://urdu-hadith.com/survey/userfiles/files/wemunilifafokuzilifafekum.pdfIn PDF document text
    • http://vintageguitar.ru/ckfinder/userfiles/files/ruruxiwo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1KS0DP0cxss/uplcv?utm_term=java+modeling+in+color+with+uml+pdfPDF 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_off0000f5f6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF5F6 11140 bytes
SHA-256: 5dd14aa980f11ef30313c1bdfd40b41548a2f270eb0b7a344caf3a2a36ea9f31
font_01_sfnt_off00010f98.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10F98 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000127aa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x127AA 17088 bytes
SHA-256: fd792ebd56cf8915b7b3b5671f9b487aa194ce998f6c8500501ad3e1d49882c4