Malicious PDF — malware analysis report

Static analysis result for SHA-256 8da1fce7c2b1fa2a…

MALICIOUS

PDF

70.6 KB Created: 2021-10-02 11:06:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-21
MD5: 824a3a0b52f923be1f804429246f58a2 SHA-1: f2f3291669641e048d53b2637b05e8357c896c53 SHA-256: 8da1fce7c2b1fa2a8e11f9f366217bd953cadc58f2c8625ee8ad0b660be7fbd1
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is identified as malicious by ClamAV and an ML classifier, with heuristics indicating embedded JavaScript and a link farm pointing to compromised CMS uploads and disposable hosting. The embedded JavaScript likely facilitates the redirection to external URLs, which are numerous and varied, suggesting an attempt to distribute malicious content or conduct phishing. The presence of multiple compromised and disposable domains indicates a pattern of evading detection and potentially hosting malicious payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://oniceh.ru/uplcv?utm_term=another+name+for+a+painter PDF link annotation
    • http://sga.cc/uploadfile/file///2021092706353120.pdfIn PDF document text
    • https://xetnghiemadndanang.com/upload/userfiles/files/8923771981.pdfIn PDF document text
    • http://katela.net/userData/board/file/70589342591.pdfIn PDF document text
    • http://graphicon.hu/wp-content/plugins/formcraft/file-upload/server/content/files/161511525e131f---4077382811.pdfIn PDF document text
    • https://www.albriug.com/static/editor/ckeditor/ckfinder/upfile/files/73009131693.pdfIn PDF document text
    • http://bingsu.ir/cache/fck_files/file/pikirazajapovadukenewojol.pdfIn PDF document text
    • http://planbmedia.hu/files/53020535010.pdfIn PDF document text
    • http://www.cuerpomenteyespiritu.es/wp-content/plugins/formcraft/file-upload/server/content/files/161415af1e2af8---37453045518.pdfIn PDF document text
    • https://egokituz.org/files/galeria/files/dofozodubadekekene.pdfIn PDF document text
    • http://optimumnieruchomosci.pl/uploads/userfiles/files/pupuninudodijadeto.pdfIn PDF document text
    • https://kalitelivideoizle.com/resimler/files/35373883948.pdfIn PDF document text
    • http://sakirnoopo.ru/wp-content/plugins/super-forms/uploads/php/files/c314e65241d967dad784a7ee91f2f4a9/boporupoxavab.pdfIn PDF document text
    • https://proektasis.gr/admin/spaw2/uploads/files/40554833182.pdfIn PDF document text
    • http://matonaklawfirm.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/nababebukupitejod.pdfIn PDF document text
    • http://www.northern-japan.com/image/upload/File/90192177637.pdfIn PDF document text
    • http://joesservicecenternj.com/userfiles/files/kisanabujiziguboj.pdfIn PDF document text
    • http://caacoding.net/wp-content/plugins/formcraft/file-upload/server/content/files/16134e027a24f2---nazemexubasanimepivo.pdfIn PDF document text
    • http://przedszkolenisko.pl/userfiles/file/fufodaxonek.pdfIn PDF document text
    • https://thefertilizerequipment.com/d/files/xaxadexasepemuxoroj.pdfIn PDF document text
    • https://htlexpress.com/ckfinder/userfiles/files/59160975201.pdfIn PDF document text
    • http://itineraire-consulting.com/ckfinder/userfiles/files/8069119177.pdfIn PDF document text
    • http://hotstamping.pl/files/file/pekunewene.pdfIn PDF document text
    • https://honghow.com/ckfinder/userfiles/files/54620556096.pdfIn PDF document text
    • http://grandrosso.com/js/upload/files/10375474633.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_off0000b3d4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB3D4 16404 bytes
SHA-256: b9a3297eb9b96d3dad5ee0054ef1c55f316e959cb62a1763f0a8230540c3558a
font_01_sfnt_off0000dd61.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD61 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f578.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF578 10392 bytes
SHA-256: 22e32699be506ea9d242d4ec06f8296e30ac9ace9ea03fd8e579bf3228dd7c56