Malicious PDF — malware analysis report

Static analysis result for SHA-256 ef55c3d09d30d16a…

MALICIOUS

PDF

70.4 KB Created: 2021-05-21 13:30:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-27
MD5: 04ff1f42d2a8f0094ffcee1e5774f73e SHA-1: 817d85e291e54ed320ed6e3bd3f695aaf5a739a9 SHA-256: ef55c3d09d30d16a842ed0ce1eb0c601612fc833d6ff75136f9086ba5452ef8c
156 Risk Score

Malware Insights

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

The PDF contains multiple heuristics indicating it is a link farm pointing to compromised websites, likely for phishing or malware distribution. The ML classifier and ClamAV detection strongly suggest malicious intent. While no scripts were explicitly extracted, the PDF structure and embedded URLs are indicative of a malicious document designed to redirect users to harmful content.

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://marciasmithconsulting.com/wp-content/plugins/super-forms/uploads/php/files/e235041c7b8ba08d44d5f2ff1b548705/jefuxow.pdf In PDF document text
    • http://allamericannursing.com/userfiles/file/95065274351.pdfIn PDF document text
    • https://jamiatulbanat.in/wp-content/plugins/formcraft/file-upload/server/content/files/1608faf3165fc0---vogafafepagovavi.pdfIn PDF document text
    • http://www.magicapro.it/wp-content/plugins/formcraft/file-upload/server/content/files/1608a96d2d9a2f---69791540637.pdfIn PDF document text
    • http://eperon-kochersberg.com/img_db/xopokawenu.pdfIn PDF document text
    • https://www.capitalroofingct.com/wp-content/plugins/formcraft/file-upload/server/content/files/16072cc6b7487e---jeduxevesek.pdfIn PDF document text
    • https://www.medipratik.com/wp-content/plugins/formcraft/file-upload/server/content/files/160823a4227316---fanox.pdfIn PDF document text
    • https://www.chesapeake-lighting.com/wp-content/plugins/super-forms/uploads/php/files/cb1d1bea639d4716f76e0f32b797e733/73829225865.pdfIn PDF document text
    • https://www.denisonlandscaping.com/wp-content/plugins/formcraft/file-upload/server/content/files/160879a71df0c0---kuguzozebizalajakiteji.pdfIn PDF document text
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608e40cf565be---69694945648.pdfIn PDF document text
    • https://eyestech.in/wp-content/plugins/super-forms/uploads/php/files/lga69k09s34nv3u55q0nfjj7md/wisexijosinopolijoxaz.pdfIn PDF document text
    • http://portalcom-b2b.es/img/user///file/_0007651001619869610.pdfIn PDF document text
    • http://www.drop-lok.com/wp-content/plugins/formcraft/file-upload/server/content/files/16075fddb06702---zewinipivoto.pdfIn PDF document text
    • http://kraljicabih.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606ccb8d2b49f---vewoxomofevu.pdfIn PDF document text
    • https://shotclock.ca/wp-content/plugins/super-forms/uploads/php/files/07c96d79ca863a1a0aa5abe77972ec8d/26651257000.pdfIn PDF document text
    • https://felix-schulze.biz/wp-content/plugins/super-forms/uploads/php/files/jkodlmtv617jj711sp5ob8itnp/40504308408.pdfIn PDF document text
    • https://markzone.az/wp-content/plugins/super-forms/uploads/php/files/ad4ioqfvjs8jao6vp45hs3u9tm/43929057570.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/Uplcv/~3/S30rS-6n6vg/uplcv?utm_term=present+modals+of+deduction+exercises+pdf+with+answersPDF 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_off0000d1ba.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD1BA 5556 bytes
SHA-256: d19cc1ebac5fd80703ce51d1aba31c902e4f74d819acb1b245242d2fa9f8f5e5
font_01_sfnt_off0000e48a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE48A 11412 bytes
SHA-256: a449f2d5c3c2904a20accfeb9bf12ad7b10ed5ec895ac96af8beb106535d9e34