Malicious PDF — malware analysis report

Static analysis result for SHA-256 71843d1d3426add9…

MALICIOUS

PDF

74.5 KB Created: 2021-07-19 11:42:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 3eca16acd4bdde232c5e16040a9a64d2 SHA-1: 05ef4321f4cd7fa9f8a431823cd660c26b2d00c9 SHA-256: 71843d1d3426add94b8a7d9e09721913d3b4d173b4e0193f010f5c483ed8dcb7
156 Risk Score

Malware Insights

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

The PDF was flagged by ClamAV as Pdf.Phishing.Trojan and an ML classifier indicated a high probability of maliciousness. The heuristics indicate the document functions as a link farm, directing users to multiple compromised or disposable hosting sites. The presence of numerous links, including those hosted on compromised CMS uploads, strongly suggests an intent to distribute malicious content or conduct phishing operations.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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 https://777mto.com/contents//files/33099203497.pdf In PDF document text
    • http://aarogyamedico.com/userfiles/file/77182988136.pdfIn PDF document text
    • https://pypconsultores.mx/userfiles/file/67029741226.pdfIn PDF document text
    • http://uniondeautoescuelas.com/wp-content/plugins/formcraft/file-upload/server/content/files/160845c8a10309---ruzojemavaketutifiba.pdfIn PDF document text
    • http://festivaldeliteraturadepereira.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b551e9396fa---tilomadiketitosuges.pdfIn PDF document text
    • http://test888.org/uploads/productsfiles/20210708080344_987eb.pdfIn PDF document text
    • http://conservationenergy.com/wp-content/plugins/formcraft/file-upload/server/content/files/160af5c32765f6---42161121820.pdfIn PDF document text
    • https://ottenburger.com/userfiles/file/luradagemebitopezarexede.pdfIn PDF document text
    • https://marcuspietrek.de/MARCUS/files/file/vixijipiwobewukezujimu.pdfIn PDF document text
    • https://agrilaui.com/userfiles/file/64291549945.pdfIn PDF document text
    • https://maydongy.com/wp-content/plugins/super-forms/uploads/php/files/a2qttjo3i6s826abjoh6gf23ef/mudozojofedufavuzotolo.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c9a1691d115---13734737848.pdfIn PDF document text
    • http://stl-hk.net/userfiles/16860737766.pdfIn PDF document text
    • https://comesa.com.pe/wp-content/plugins/super-forms/uploads/php/files/2afosc0923d6ora27p2b10i6f1/vusep.pdfIn PDF document text
    • http://bhhangkhong.com/upload/images/files/jiboninufunezoje.pdfIn PDF document text
    • http://etasystem.net/userfiles/files/16578630209.pdfIn PDF document text
    • http://prodesign31.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16092548c40abc---limojixo.pdfIn PDF document text
    • http://luvnchrlysenglishtoys.com/clients/861429/File/97534031381.pdfIn PDF document text
    • https://bibonatura.hu/ckfinder/userfiles/files/mumovigudijurovavoxulo.pdfIn PDF document text
    • http://energo-market.ru/sadm_files/gijab.pdfIn PDF document text
    • http://elonsummerstorage.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a7f48a704ec---17587980541.pdfIn PDF document text
    • https://drmiamiconnect.com/wp-content/plugins/super-forms/uploads/php/files/cf252cd99c79255e6a02280e3e89e3a0/katexogeje.pdfIn PDF document text
    • http://kco.su/userfiles/file/bakikolerunuri.pdfIn PDF document text
    • http://mtecommerce.it/public/news/file/judidepewigeperux.pdfIn PDF document text
    • http://truhlarstvisollner.cz/data/file/rotexedizudisewotagibixe.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/PmAiG5ZyT-k/uplcv?utm_term=science+8+mirrors+worksheet+answer+keyPDF 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_off0000c2d7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC2D7 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000dae9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDAE9 15648 bytes
SHA-256: 1282df08f5e90dd8a2de8ad0b7da55a889cd4f68908fe2ee1dd30c99db8fb02a
font_02_sfnt_off000102fe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x102FE 11024 bytes
SHA-256: 0215adc12427f3bbb6f6ef253135e257e0d97273a9ae7ec8ffebc92948d55448