Malicious PDF — malware analysis report

Static analysis result for SHA-256 5c7b4f5873be73f3…

MALICIOUS

PDF

73.9 KB Created: 2021-06-11 13:02:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-27
MD5: 17d828835b94e94ab98ba26e5d14c812 SHA-1: 45435c2a9f8684b6c889d762b61149c2797f8a56 SHA-256: 5c7b4f5873be73f3ecdd43e7caf255512119473e845ee17b7dddb8a6e9c7dd51
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous links to external websites, many hosted on compromised CMS platforms or disposable domains, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or distributing further malware. The embedded URLs and the PDF's structure align with techniques used to obscure malicious destinations.

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://crewmak.ru/uplcv?utm_term=windows+xp+startup+mp3 PDF link annotation
    • http://school19-zav.ru/userfiles/file/wiwen.pdfIn PDF document text
    • https://www.uniqueartzz.com/wp-content/plugins/super-forms/uploads/php/files/1vvkloqaab4phmpl95gvg9dkr5/sejiro.pdfIn PDF document text
    • http://bright-mineral.com/uploadfile/file/2021051614523861.pdfIn PDF document text
    • https://propbrains.com/wp-content/plugins/super-forms/uploads/php/files/86tgjlslh5rmrmh8p4517nad30/65228503724.pdfIn PDF document text
    • http://cityhigh78.com/clients/2/2d/2ddbae4fb74c169819b3574d76e4e264/File/zuvemivokekepigezipur.pdfIn PDF document text
    • http://bezagsecurity.cz/userfiles/gopaxezexerutofivi.pdfIn PDF document text
    • http://ghalemdi.com/userfiles/file/fotibusagaxojisorib.pdfIn PDF document text
    • https://schreinerheusi.de/wp-content/plugins/formcraft/file-upload/server/content/files/1606cbad640b46---347806587.pdfIn PDF document text
    • https://www.hdcorp.com.br/wp-content/plugins/super-forms/uploads/php/files/ff69b3lf5vmva7pvk1206rk5n4/tuviw.pdfIn PDF document text
    • https://addsfly.com/userfiles/file/37380641441.pdfIn PDF document text
    • http://peusch.lu/userfiles/files/68437675131.pdfIn PDF document text
    • http://agiusfuneraldirectors.com/files/file/lawefetuma.pdfIn PDF document text
    • http://aarogyamedico.com/userfiles/file/48364037959.pdfIn PDF document text
    • https://esteticarcare.com/wp-content/plugins/super-forms/uploads/php/files/20410e41d68d61134c795079978277b7/60939718394.pdfIn PDF document text
    • https://nicemexico.net/wp-content/plugins/formcraft/file-upload/server/content/files/160aacae41c129---25192086821.pdfIn PDF document text
    • http://www.pirac.org/wp-content/plugins/super-forms/uploads/php/files/195f31b2573163888ea4904555ad7e69/xonuwila.pdfIn PDF document text
    • https://sipare.com.ar/wp-content/plugins/super-forms/uploads/php/files/1dqvo01efiefq9oh2dhg321n80/pimofirurejopovogep.pdfIn PDF document text
    • http://www.mondzorgvesa-voorschoten.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160997d17cc5c4---kowoganoxirur.pdfIn PDF document text
    • https://ebooksweb.net/files/file/gelepiwiviparigumumuzazef.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_off0000e3da.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE3DA 5408 bytes
SHA-256: 4b4beaa8a710fe03f214f4b5d2573102c4fc353f8865c69f66508dce73147c6a
font_01_sfnt_off0000f646.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF646 11152 bytes
SHA-256: d6b9a7966f33a5e33a202a0e93078e5feec00abace23c904d53b36a0c79f9cb0