Malicious PDF — malware analysis report

Static analysis result for SHA-256 e539d8d008fcbfb8…

MALICIOUS

PDF

71.3 KB Created: 2021-09-17 12:15:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 015138b415d97ede4ff2c41780f28d7e SHA-1: 8be214279932844f5768834b0c6b663ead37a65a SHA-256: e539d8d008fcbfb89bbe91b4ee56c362240c7206d2ec44d68d84dca7239c53ac
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised websites or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. The heuristic PDF_SEO_DISPOSABLE_LINK_FARM specifically highlights the nature of the links as a non-clustered link farm on disposable hosting.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://nomylo.ru/uplcv?utm_term=live+wallpaper+league+of+legends+android PDF link annotation
    • http://techbico.vn/uploads/image/files/69463905862.pdfIn PDF document text
    • http://budoprojekt.eu/obrazy/file/gizenurogukozumudebor.pdfIn PDF document text
    • https://trsbarriersdirect.com/wp-content/plugins/super-forms/uploads/php/files/b9pv1nr60g35ibf4jlirkar54p/lazibim.pdfIn PDF document text
    • http://pieseclimaauto.com/files/file/najepifomidosegopekubugij.pdfIn PDF document text
    • http://internationalnetworksolutions.net/files/In PDF document text
    • http://morebricks.com/ckfinder/userfiles/files/78766729118.pdfIn PDF document text
    • https://sibirprokat.ru/ckfinder/userfiles/files/nagubuzibovavixuwixawawa.pdfIn PDF document text
    • https://iamtimeshare.com/userfiles/file/9879251141.pdfIn PDF document text
    • https://actaviaserica.org/board/file/files/siviz.pdfIn PDF document text
    • http://zhihepvb.com/upload/ckimg/files/202109090455126883.pdfIn PDF document text
    • http://polymer-optix.de/userfiles/file/tonovelamifazuzofasiw.pdfIn PDF document text
    • http://proclima-membranes.ru/userfiles/file/velenisijonogob.pdfIn PDF document text
    • http://a2hgghk.handylover.com/upload/files/89881381506.pdfIn PDF document text
    • https://jordanadams.com/ckfinder/userfiles/files/zomivemusinuvozabej.pdfIn PDF document text
    • https://egyediajandekotletek.hu/mvc/userfiles/file/48602471304.pdfIn PDF document text
    • http://ok-poland.com/userfiles/file/mebojorofijokurixedi.pdfIn PDF document text
    • https://www.rosebankprimary.co.za/inc/ckfinder/userfiles/files/nuteselite.pdfIn PDF document text
    • https://berbagiangka.com/contents/files/11212709189.pdfIn PDF document text
    • http://netart.hu/userfiles/file/dinadamurisaniki.pdfIn PDF document text
    • https://joepromenshealth.com/wp-content/plugins/super-forms/uploads/php/files/aba80e7f0620197aae0d4ac088291d99/86820223520.pdfIn PDF document text
    • http://centrons.com/uploaded/file/1768978475612f94bdc5c50.pdfIn PDF document text
    • http://www.nisbd.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613b1bb8e4d0d---66950923763.pdfIn PDF document text
    • http://woodlander.sk/grafika/file/52560851363.pdfIn 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://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_off0000b78c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB78C 15532 bytes
SHA-256: bad2a828d05f9d427f976e97da7fe589de788cfb30d9228b9eb4bea5932edbe7
font_01_sfnt_off0000df3d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF3D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f754.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF754 10784 bytes
SHA-256: 43ba333792a9fb156744761e1d2b2d43dce4223bb4fcec261e898884f5b83e87