Malicious PDF — malware analysis report

Static analysis result for SHA-256 a44ac8a5e2d686b0…

MALICIOUS

PDF

79.6 KB Created: 2021-09-06 18:56:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: b42055b72f979f810fcc35ca67f55d30 SHA-1: e368a6e4d34bd9fc7c6e51584efbba0b68cbd327 SHA-256: a44ac8a5e2d686b05c4b514f661b28423a6b97e9263f03e6312984484781c848
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm pointing to compromised WordPress upload storage and other potentially malicious URLs. The PDF structure and embedded content suggest it is designed to redirect users to external sites, likely for phishing or to download further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9846

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://www.fullmooneye.com/wp-content/plugins/formcraft/file-upload/server/content/files/160cddd4b0548b---86173601838.pdf In PDF document text
    • http://rideabikenews.com/user_img/files/lexukavuwozakoxirulomat.pdfIn PDF document text
    • https://primer-spb.ru/files/files/guzovej.pdfIn PDF document text
    • https://islandsvefir.is/wp-content/plugins/super-forms/uploads/php/files/2mk5h1sg18e14irjbfrtqdn65r/1933081896.pdfIn PDF document text
    • http://www.rebranded.tv/wp-content/plugins/formcraft/file-upload/server/content/files/160ccf24a758ea---91847462112.pdfIn PDF document text
    • https://camile.vn/wp-content/plugins/super-forms/uploads/php/files/erir2p4m588sso1u7i7td7u0fq/luvodavepuporuzimip.pdfIn PDF document text
    • https://ancoraeducacion.com/images/7142237219.pdfIn PDF document text
    • http://fashioncenterpoint.com/wp-content/plugins/super-forms/uploads/php/files/eb9fed99a9f28c9bb2672726ef1f9a0a/46891509442.pdfIn PDF document text
    • http://archetipoingegneria.it/userfiles/files/zamudagegiru.pdfIn PDF document text
    • https://www.apartamentselsllacs.com/wp-content/plugins/super-forms/uploads/php/files/jap9n37sirmojtgds5cj4pg3jp/tupol.pdfIn PDF document text
    • https://www.westcountrystoves.co.uk/wp-content/plugins/super-forms/uploads/php/files/b20970e4d9ca17028d1638f57f2e1a8a/fepezazimamapokexureviw.pdfIn PDF document text
    • https://sketchup360.vn/wp-content/plugins/super-forms/uploads/php/files/qr38tafbr753ak1dsn7kv2c7u8/wosimuvep.pdfIn PDF document text
    • http://deurwater.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c3fbb23c47e---44735665404.pdfIn PDF document text
    • https://masini-de-ambalat.ro/images/userfiles/fojedapotonopanexo.pdfIn PDF document text
    • http://clinicacomciencia.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160c759023c32c---21105504909.pdfIn PDF document text
    • https://agrotehholding.ru/wp-content/plugins/super-forms/uploads/php/files/97d0cf97a434299cfd90aaaee2a85aa3/sonino.pdfIn PDF document text
    • http://cybernet-ap.com/UserFiles/File/90956368308.pdfIn PDF document text
    • https://bodwellassociates.com/wp-content/plugins/super-forms/uploads/php/files/81c195641232aa4b5f7fe428da0e2155/kikaguzugodozudijajuno.pdfIn PDF document text
    • http://abwrva.com/uploads/files/nivuzesoxopawami.pdfIn PDF document text
    • http://mesotects.com/wp-content/plugins/formcraft/file-upload/server/content/files/16072ae770dc4f---30464452448.pdfIn PDF document text
    • https://menlopark.com/wysiwygfiles/file/xikan.pdfIn PDF document text
    • https://www.duffylighting.com/wp-content/plugins/super-forms/uploads/php/files/70b2afe7efb71e6f9c01f5ea3cee3f7e/pomudugalodobude.pdfIn PDF document text
    • http://manchetenewsms.com.br/ckfinder/userfiles/files/19421772887.pdfIn PDF document text
    • https://acethamessecurity.co.uk/wp-content/plugins/super-forms/uploads/php/files/18b5c161c39f63bd3286c56d9b0a651e/xofox.pdfIn PDF document text
    • http://aadcnfgl.netsociality.com/upload/files/11324581015.pdfIn PDF document text
    • https://noks.cz/wp-content/plugins/formcraft/file-upload/server/content/files/160793ba42db59---73258830854.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/DOqCt-cVA4I/uplcv?utm_term=how+to+convert+pdf+to+word+using+cutepdf+proPDF 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_off0000d35a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD35A 10832 bytes
SHA-256: efac4f46dc3a80e0342f62ca6535cb56ab756926c68ff433254a0baa99edd480
font_01_sfnt_off0000ec46.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC46 17216 bytes
SHA-256: 977c70c8dce9cd49f360bab6a6592bd66fc7cead34ebd7a3c83c57442b3cd9f2
font_02_sfnt_off000118b5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x118B5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1