Malicious PDF — malware analysis report

Static analysis result for SHA-256 efd9397ad5900936…

MALICIOUS

PDF

71.2 KB Created: 2021-04-27 22:22:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-20
MD5: 6dd42ddca1b3c18d67f0dd553a968590 SHA-1: b9cbb20a74f721818fe972855ae509aa77f3ddc3 SHA-256: efd9397ad590093634a7c1b5694963f691ed9db1bffe958e35d895746867c459
156 Risk Score

Malware Insights

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

The PDF contains numerous links to compromised WordPress sites, indicating a link farm designed to distribute malware or phish users. The ClamAV detection and ML classifier strongly suggest malicious intent, likely related to phishing or malware delivery. Although no scripts were explicitly extracted, the presence of embedded URLs and the nature of the heuristics point towards a malicious document.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 6

  • 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.
  • 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://reflexlighting.com/wp-content/plugins/super-forms/uploads/php/files/1044caa3c91c3add7562cd51c873d644/tofukubikikelikunapevetig.pdf In PDF document text
    • https://enville.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607a6202310b0---bomubobajebonazatefakobu.pdfIn PDF document text
    • https://beaumont-residence.com/wp-content/plugins/super-forms/uploads/php/files/mmvm6v79ce4k4toangp2mhmfds/gigur.pdfIn PDF document text
    • https://www.kalirich.com/wp-content/plugins/super-forms/uploads/php/files/1eu8it7lucol0gkte9d5c18u77/5209944491.pdfIn PDF document text
    • https://www.darrellstuckey.com/wp-content/plugins/formcraft/file-upload/server/content/files/160800734c564d---3064786855.pdfIn PDF document text
    • https://refour.dk/wp-content/plugins/super-forms/uploads/php/files/c6e679855ff83dc3546fdb79a43e046a/fenubodugisuv.pdfIn PDF document text
    • https://www.andrecampbell.ca/wp-content/plugins/super-forms/uploads/php/files/b581495cd1f5f644bfafa03cfb6807a5/29373674733.pdfIn PDF document text
    • http://www.asejnrtigers.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1606d3c6b1695d---64215630792.pdfIn PDF document text
    • http://www.uvhk.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608353bf6094e---69720375359.pdfIn PDF document text
    • http://maidnheaven.com/wp-content/plugins/formcraft/file-upload/server/content/files/16076bd5d7c30f---94835858552.pdfIn PDF document text
    • http://www.webtony.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160838f147420b---38667690214.pdfIn PDF document text
    • https://www.sehersirin.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d375347628---narileluwonaditegifomo.pdfIn PDF document text
    • http://informerfitness.com/wp-content/plugins/super-forms/uploads/php/files/9322ba9f9e1cdfce3e757c7f4b9483bf/xalukokomipeletakoporujin.pdfIn PDF document text
    • https://alllegaltask.com/wp-content/plugins/super-forms/uploads/php/files/sb7n1efg5plfc85uo7lalv1keo/22727035300.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/ngfLrbzwjls/uplcv?utm_term=classroom+games+for+teaching+english+pdfPDF 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d8f9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD8F9 5476 bytes
SHA-256: b57219b3776792ba215baf90f6861f26e8456086bfd8bb066907c9781b3faa86
font_01_sfnt_off0000eb68.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB68 10520 bytes
SHA-256: 82adf5babd5bb27999494bb56fc50251670a1656a41f3492f63b6d4d68901d51