Malicious PDF — malware analysis report

Static analysis result for SHA-256 8211a8b4845ebf40…

MALICIOUS

PDF

77.5 KB Created: 2021-08-17 20:44:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 48cc2f40e975596011945a00ee3f9225 SHA-1: 584b6ab10c2d0f48c266eb724e2880ab965fcc74 SHA-256: 8211a8b4845ebf4081c774461a6a973f92414c418dd97defc6af225f59e236c2
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains a link farm directing to multiple compromised WordPress sites, identified by heuristics like 'PDF_SEO_DISPOSABLE_LINK_FARM' and 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM'. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution. No scripts were extracted, but the structure and URL patterns are typical of a malicious document used for initial access.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://microfocus-realize2020mea.com/wp-content/plugins/super-forms/uploads/php/files/3710d9f2539f7d6c18d385cde1cb7098/bixisor.pdf In PDF document text
    • https://ols.lighting/wp-content/plugins/super-forms/uploads/php/files/b2982a7cd3a005d54357a647a693ad50/16007967285.pdfIn PDF document text
    • https://agsposure.org/wp-content/plugins/super-forms/uploads/php/files/be4f05eee604f86958b0024784602493/nukefesutosixijitevabi.pdfIn PDF document text
    • https://www.hotel-palladium.gr/wp-content/plugins/super-forms/uploads/php/files/qcj5j57vav252k25cs7nkm2ncj/83531429840.pdfIn PDF document text
    • http://bukharasuwanee.com/sites/default/files/file/sotumuzevav.pdfIn PDF document text
    • http://gayaarchi.com/userfiles/file/20210716193004.pdfIn PDF document text
    • https://realimpacto.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16091321d7fa25---tubulogijopaj.pdfIn PDF document text
    • https://lakecountyoralsurgery.com/wp-content/plugins/formcraft/file-upload/server/content/files/160895f7eababb---dawojujodomugotufetided.pdfIn PDF document text
    • http://atenngo.com/admin/sites/site/documents/29457095951.pdfIn PDF document text
    • http://gachbinhduong.com/upload/file/juxelegujenuwuwir.pdfIn PDF document text
    • http://dzstock.com/Upfiles/file/75131092984.pdfIn PDF document text
    • http://leinerpakgelatine.com/survey/userfiles/files/sinufirixi.pdfIn PDF document text
    • http://dafangtour.com/fckeditor/userimages/file/93336603588.pdfIn PDF document text
    • http://askaudit.ru/price/titagafikirinomivakeg.pdfIn PDF document text
    • https://www.histoiresdegroupes.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a8c63f9a60e---bolupesojodutufasejugovuw.pdfIn PDF document text
    • https://thesmithgrouphouston.com/wp-content/plugins/super-forms/uploads/php/files/9dc764eed18aef863199d3ffcfbb3ea2/balexiwa.pdfIn PDF document text
    • http://www.theagentpipeline.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bdcb2c88f29---gumijunodusinonuxom.pdfIn PDF document text
    • https://www.frankreich-ferien.ch/wp-content/plugins/formcraft/file-upload/server/content/files/1607b70b11ea0e---gejij.pdfIn PDF document text
    • https://www.bevillelecomte.com/ckfinder/userfiles/files/15742522617.pdfIn PDF document text
    • http://trenermichal.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160c1457b0a816---95223686938.pdfIn PDF document text
    • http://abwmountvernon.com/uploads/files/ginonevimekuzowibidud.pdfIn PDF document text
    • http://capthepcongtrinh.com/uploads/news/files/rinejerabafupowevo.pdfIn PDF document text
    • http://www.sarajevo-inn-grunewald.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bec17f4e3a7---ledugupos.pdfIn PDF document text
    • http://www.irrv.org/uploads/files/40001307741.pdfIn PDF document text
    • http://architettipassarinmarzotto.com/userfiles/files/wujavawebiwu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/zMnd8XtcwSM/uplcv?utm_term=how+to+convert+square+meter+to+cubic+feetPDF 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_off0000cc39.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCC39 15856 bytes
SHA-256: 462aa0be2500b85e6e5b640ffd4a9e5ee67a6538b1fbd8ccfe13ac36eab287f0
font_01_sfnt_off0000f528.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF528 10980 bytes
SHA-256: be9fe716a8c46603da7539071aff47a4630fc5e9bfb7e1b8e36084dd204a9233
font_02_sfnt_off00010eb5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10EB5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1