Malicious PDF — malware analysis report

Static analysis result for SHA-256 d5c03e146a31dee5…

MALICIOUS

PDF

75.5 KB Created: 2021-06-23 18:19:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-11
MD5: e5c914c9c7e6d111846309877628c8ce SHA-1: 0f9ddd67c1eccb1e6e7e5deb49fc6d6606fa7733 SHA-256: d5c03e146a31dee53cd1842bdd83ec827c0f08277f7d62d746ff85825f18a833
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

This PDF file was flagged by multiple heuristics and an ML classifier as malicious, with ClamAV identifying it as Pdf.Phishing.Trojan. The numerous embedded URLs, many pointing to compromised WordPress sites or disposable hosting, suggest a link farm designed to redirect users to malicious content. The document body, though heavily obfuscated, contains references to wkhtmltopdf and a date, indicating it was likely generated programmatically to serve as a lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://queure.ru/uplcv?utm_term=how+to+make+a+note+pdf+on+iphone PDF link annotation
    • http://akvari-um.ru/userfiles/file/53946319530.pdfIn PDF document text
    • https://ivanda-commerce.hr/userfiles/file/peperoju.pdfIn PDF document text
    • http://orgue-chantepie.info/FCKeditor/upload/file/jaganirusufizi.pdfIn PDF document text
    • https://www.generalutilities.com/wp-content/plugins/formcraft/file-upload/server/content/files/160809647abcc3---49283913963.pdfIn PDF document text
    • http://www.ncstarim.com.tr/wp-content/plugins/super-forms/uploads/php/files/meqhlnvhp5o19eb07vadh32c13/47382226694.pdfIn PDF document text
    • http://vitalenzyme.com/uploads/fckupload/file/bovugigofizu.pdfIn PDF document text
    • https://www.numberoneporthill.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160be30460d427---makut.pdfIn PDF document text
    • https://webmodels.studio/wp-content/plugins/formcraft/file-upload/server/content/files/160d2869fa50be---zijibamixitanafi.pdfIn PDF document text
    • http://maroba-zirndorf.de/file/xazozefuzosarivibewijad.pdfIn PDF document text
    • http://harposwebdesign.nl/app/webroot/files/userfiles/files/geriwutopavowoxawusanavox.pdfIn PDF document text
    • https://e-lightingcontrols.com/wp-content/plugins/super-forms/uploads/php/files/81a94d04d5381e1afb96a61106075ed0/ninixusigabepujakesajo.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b7a0feb1da5---51865025208.pdfIn PDF document text
    • http://porpora.info/imagenes/imagenes_contenidos/%5C/rifofatapiwuwiwukumo.pdfIn PDF document text
    • https://tcufroghouses.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608315b40c2a9---37220144263.pdfIn PDF document text
    • https://assurancemauricie.com/wp-content/plugins/formcraft/file-upload/server/content/files/16090b4a608cb4---jagabesewetanixuvijavuje.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000dd60.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD60 4880 bytes
SHA-256: 034cbb5669a766529c5926c596595a7fd889d565e17a343f272b4d537c56aab0
font_01_sfnt_off0000edd9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEDD9 10888 bytes
SHA-256: 8407abac79b41ee2bdf8f865a11e11e4e1dbbe7f60b1cbf38c7da233c1612cf3
font_02_sfnt_off000112ea.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x112EA 4324 bytes
SHA-256: 7f6049e5011acf0e8581793f2bc2bb947aac2929fdb77abc318b2a6155c1ef71