Malicious PDF — malware analysis report

Static analysis result for SHA-256 40cda93f31a103d9…

MALICIOUS

PDF

80.8 KB Created: 2021-08-30 17:48:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 20f5adbbe66507dd4138b60aebb24e86 SHA-1: ac78f444144cb2b0f4f53a19f6823227290afe46 SHA-256: 40cda93f31a103d931e79a87e4f51ddda4c3e24c0719c086b2abf0e979c11ec9
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains numerous external links, many pointing to compromised WordPress sites, suggesting a phishing or redirection attempt. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to lure users to malicious content or exploit vulnerabilities. No scripts were extracted, but the structure and URL patterns are consistent with a phishing campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9995

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://apexforestservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612b6fe4bf33a---zavebidujoropilekoked.pdf In PDF document text
    • https://bursaceviritercume.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608a379e7002c---34085206353.pdfIn PDF document text
    • http://ehomerealestate.org/images/file/37972788990.pdfIn PDF document text
    • http://le-bouquet.be/userfiles/files/85093763779.pdfIn PDF document text
    • http://tfh-filter.hu/_user/file/66628763558.pdfIn PDF document text
    • http://hopkim.vn/upload/files/64493252019.pdfIn PDF document text
    • https://lakeshoresmilesdentistry.com/wp-content/plugins/super-forms/uploads/php/files/1rsf70ov1q7ijqjh9l42lq87n3/sewusogikevenimix.pdfIn PDF document text
    • https://agilitynd.com/wp-content/plugins/super-forms/uploads/php/files/d607d389e386ac960989d9d2c1330e2a/gajujeve.pdfIn PDF document text
    • https://evg-prague.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1607ef56d4ad0b---rutuvukejapivuledag.pdfIn PDF document text
    • https://siahotel.com/userfiles/files/30264771460.pdfIn PDF document text
    • https://mantyobras.com/userfiles/file/89926354627.pdfIn PDF document text
    • http://okwecare.com/usr/userfiles/files/lerajuki.pdfIn PDF document text
    • http://spreewaldatelier.de/img/editor/file/gopagurananela.pdfIn PDF document text
    • https://rent-1.es/ckfinder/userfiles/files/64925509403.pdfIn PDF document text
    • http://ever0036.com/assets/uploads/ckedit/files/20210728154955.pdfIn PDF document text
    • http://stellar.ru/ckfinder/userfiles/files/deropero.pdfIn PDF document text
    • http://sweethomedelivery.com/ckeditor/ckfinder/core/connector/php/uploads/files/3282018879.pdfIn PDF document text
    • https://atcotourismtravel.com/userfiles/file/45849119482.pdfIn PDF document text
    • http://ahlhy.com/uploads/file/051552087511.pdfIn PDF document text
    • http://chiangmai-clean.com/user_img/files/34435084822.pdfIn PDF document text
    • http://abwpetersburg.com/uploads/files/gitofuzalubenu.pdfIn PDF document text
    • http://tranindo.com/Uploads/userfiles/files/ledos.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/YTWXjIUwRh0/uplcv?utm_term=first+order+circuit+examplesPDF 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_off0000d38c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD38C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000eba3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEBA3 10748 bytes
SHA-256: 8a7b5181f8e0ec845ac1e1101702d1f48a28b360c66f884168820a50e024e43a
font_02_sfnt_off00010464.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10464 18856 bytes
SHA-256: 7bd218a2469cf4385c77a3f961b9d6dcae871b05acb0fa8b58d6db0ad58a9270