Malicious PDF — malware analysis report

Static analysis result for SHA-256 4c88c22b06ba335f…

MALICIOUS

PDF

83.2 KB Created: 2021-07-13 18:50:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: bd355e30421d0c8a631515ea75008c6a SHA-1: 4793f1938b907a356230bb5d4bcab96cf6c8aced SHA-256: 4c88c22b06ba335f5834aa55553b4df804957dffee2b9d5834305027d20d8730
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains a link farm pointing to multiple compromised WordPress sites, likely serving as a distribution point for malicious content or phishing lures. The presence of numerous external URIs and the PDF_SEO_DISPOSABLE_LINK_FARM heuristic indicate a deliberate effort to create a network of redirectors.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://korzayithalat.com/spot/admin/fckeditor/userfiles/file/lisuxolekuba.pdf In PDF document text
    • https://hartwellcook.com/wp-content/plugins/super-forms/uploads/php/files/d84c22d3b6c10649cf28ffb5bff29162/kajiv.pdfIn PDF document text
    • https://adbetelparaguay.com/wp-content/plugins/super-forms/uploads/php/files/295095df398deb1c0f5b40f6689d536e/nokiwabebotetowuwitima.pdfIn PDF document text
    • http://fixafilm.se/userfiles/file/funuduxagazufog.pdfIn PDF document text
    • http://getvisa.ru/images/File/sujironegaxeroxuga.pdfIn PDF document text
    • https://hoovermaids.com/wp-content/plugins/super-forms/uploads/php/files/a80da4b02804a2e983d47eed1cee22a8/xepobabimijifew.pdfIn PDF document text
    • http://seanmore.com/userData/board/file/zavizemav.pdfIn PDF document text
    • https://aquaticlandscape.com/wp-content/plugins/formcraft/file-upload/server/content/files/16094d437d17f4---79710425047.pdfIn PDF document text
    • http://selfmadefilms.nl/userfiles/files/57947956887.pdfIn PDF document text
    • http://sys-svinding.dk/userfiles/file/soxiduwugedufakasaturo.pdfIn PDF document text
    • https://roadtoring.com/wp-content/plugins/super-forms/uploads/php/files/a7d2e4676825410761bb98960d036ff9/6883397380.pdfIn PDF document text
    • https://118highschool.am/wp-content/plugins/super-forms/uploads/php/files/176f69cad911fc95c7b851c755d2ffe5/81033577272.pdfIn PDF document text
    • http://www.trafikyaren.com/wp-content/plugins/super-forms/uploads/php/files/4h5mmtieaa1e015uqlj7ctkfv5/46916027249.pdfIn PDF document text
    • https://clumba-indoor.ru/files/files/xiwotugeraxuji.pdfIn PDF document text
    • https://renesens21.com/ressources/upload/files/savovilefas.pdfIn PDF document text
    • http://www.idenet.net/wp-content/plugins/formcraft/file-upload/server/content/files/1606cb38975fa9---rozowazazapurog.pdfIn PDF document text
    • https://playgametoday.ru/wp-content/plugins/super-forms/uploads/php/files/d958b7e6a0726811b88bc48d802c6293/bebipe.pdfIn PDF document text
    • http://www.sunarmisir.com.tr/wp-content/plugins/super-forms/uploads/php/files/oqqacfigecmbdq8mlkdtel3g24/goxadexo.pdfIn PDF document text
    • http://accessprecision.com/userfiles/file/37229180704.pdfIn PDF document text
    • http://fixafilm.se/userfiles/file/45226827299.pdfIn PDF document text
    • http://misosmile.com/upload/editor/files/13762562393.pdfIn PDF document text
    • https://engravestone.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c71c8e665df---peduzuripowinegene.pdfIn PDF document text
    • http://www.photobreak.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160e4eabc3176c---8895114170.pdfIn PDF document text
    • https://t2sc.me/userfiles/84403475509.pdfIn PDF document text
    • https://www.generalutilities.com/wp-content/plugins/formcraft/file-upload/server/content/files/160849c1fd230f---27201038997.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/fzgW7-mxBc0/uplcv?utm_term=the+bell+boysPDF 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_off0000e290.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE290 9868 bytes
SHA-256: d14f48c99b8907d15c79ec9e7621c58727065fa443b1a351e3f48cc5680c29f7
font_01_sfnt_off0000f86e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF86E 17576 bytes
SHA-256: 5275ea4e0f87762385cad6f4ed4fabb667390b830dbb298ebb1b284294321bfe
font_02_sfnt_off00012637.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12637 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1