Malicious PDF — malware analysis report

Static analysis result for SHA-256 4473844c36f74d56…

MALICIOUS

PDF

81.3 KB Created: 2021-06-10 03:08:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-25
MD5: f6e90dddd6acb0982d36e63bc96183aa SHA-1: 8a9f8a7b0d6734f7d567a416a07ee3b28a297b66 SHA-256: 4473844c36f74d56bf31a3232a78ba40e592dc3b19c1d2e912185f853fee5983
156 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier. It functions as a link farm, containing numerous embedded URLs that point to compromised websites, many of which appear to be WordPress installations. The primary purpose seems to be directing users to potentially malicious content or phishing sites.

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://ketchas.ru/uplcv?utm_term=photo+editing+cb+background+hd PDF link annotation
    • https://www.hagensmarketing.com/wp-content/plugins/formcraft/file-upload/server/content/files/16077ae57b8202---vinagalebekawijo.pdfIn PDF document text
    • https://www.geosuiteonline.de/wp-content/plugins/formcraft/file-upload/server/content/files/160b39428193ae---21538265107.pdfIn PDF document text
    • https://www.cir.cloud/wp-content/plugins/formcraft/file-upload/server/content/files/1607700840ea34---xedivoguponun.pdfIn PDF document text
    • https://ecomassage.pt/wp-content/plugins/super-forms/uploads/php/files/pcbv5h5dck375dhto6qlij7op7/37891333958.pdfIn PDF document text
    • https://maydongy.com/wp-content/plugins/super-forms/uploads/php/files/2bhtq1aqb335iqud1tt41gjgtk/gexekozuw.pdfIn PDF document text
    • http://kaushalacademy.org/ckfinder/userfiles/files/90578736366.pdfIn PDF document text
    • https://holzhaus-suedtirol.it/wp-content/plugins/formcraft/file-upload/server/content/files/160846da734ee0---78430321017.pdfIn PDF document text
    • http://drapa-technika.cz/UserFiles/File/risodokin.pdfIn PDF document text
    • https://shinyjewellers.com/wp-content/plugins/super-forms/uploads/php/files/ijmcgollpr26vs2trddcoqnsd4/71699615934.pdfIn PDF document text
    • https://tkpmission.org/wp-content/plugins/formcraft/file-upload/server/content/files/160b2357934d00---dowogefetuno.pdfIn PDF document text
    • http://bajcsidavidfoto.com/_user/file/25659159378.pdfIn PDF document text
    • http://assushop.com/userfiles/assushop.com/file/2689518475.pdfIn PDF document text
    • https://alenakovalchuk.ru/wp-content/plugins/super-forms/uploads/php/files/094d0b26039692d5e71f6913921ad2ae/97343355948.pdfIn PDF document text
    • https://aawyx.com/sites/default/imageuser/file/supotub.pdfIn PDF document text
    • https://amalighting.com/wp-content/plugins/super-forms/uploads/php/files/7ce332023f986f7433b61a9d4dfc2591/denirujufuvut.pdfIn PDF document text
    • https://aryaayur.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b7e5ce25acb---67402073178.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000101fd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x101FD 5196 bytes
SHA-256: f27a08aed3bc853269e63b6cb2be2cb7ded6087427e8c02ea6da4b2b0f82048e
font_01_sfnt_off000113a2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x113A2 10592 bytes
SHA-256: 0991a6170370320d9352c0f77e5556398e2df3e490f28463a99e399f9cc7f9f3