Malicious PDF — malware analysis report

Static analysis result for SHA-256 ca5a73bb8172849d…

MALICIOUS

PDF

95.0 KB Created: 2021-09-22 19:31:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 98fe3dfd3a2b0ddbefdc2417f7404c6b SHA-1: c5d15d70b7a1c31f7e8c38a098b4b1f8ca5afc2a SHA-256: ca5a73bb8172849d37851185ca8baaeeff648f3ff49de90dc0e87e2669ca37ba
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The ML classifier and ClamAV detection strongly indicate maliciousness. The PDF contains numerous links, many pointing to disposable hosting or compromised CMS uploads, suggesting a link farm designed to redirect users. The presence of external URIs and the overall structure point towards a phishing or malware distribution scheme, likely initiated via spearphishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9957

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://oniceh.ru/uplcv?utm_term=the+suicide+squad+2+online PDF link annotation
    • http://lafiestadelmoto.cz/files/file/dufofaxidonumixiguvik.pdfIn PDF document text
    • http://nbc.com.vn/ckfinder/userfiles/files/18148392047.pdfIn PDF document text
    • http://meuble-tunisie.com/userfiles/file/20666849326.pdfIn PDF document text
    • http://stopasbestos.ca/wp-content/plugins/formcraft/file-upload/server/content/files/161371ecfb37c0---73128417963.pdfIn PDF document text
    • http://german-ex.com/images/blog/file/sowesararebudokelivogu.pdfIn PDF document text
    • https://namhunglogistic.vn/site/files/25031482428.pdfIn PDF document text
    • http://www.toptehnik.si/images/52918900836.pdfIn PDF document text
    • https://sodigital.it/wp-content/plugins/formcraft/file-upload/server/content/files/16143c1563df6f---lasilawawar.pdfIn PDF document text
    • https://iqrainternationalschool.org/_assets/files/6472838793.pdfIn PDF document text
    • http://geometrabottero.it/userfiles/files/zizejifonivabi.pdfIn PDF document text
    • https://mavismanagement.com/wp-content/plugins/formcraft/file-upload/server/content/files/16134284bdd064---86034755757.pdfIn PDF document text
    • https://www.histoiresdegroupes.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613b7e51c3026---jojekisoligazavuw.pdfIn PDF document text
    • http://resheto.ru/users_images/fck/file/gefisef.pdfIn PDF document text
    • https://mgc.to/sites/web/upload/files/71728089616.pdfIn PDF document text
    • https://olterus.net/contents/files/kudonokumefivepuwomugu.pdfIn PDF document text
    • https://www.theknowledgeonline.com/files/lib/ckfinder/userfiles/files/jarifafo.pdfIn PDF document text
    • http://dallapietamarchisio.it/userfiles/files/55380248810.pdfIn PDF document text
    • http://aranykoronakft.hu/userfiles/file/34867231842.pdfIn PDF document text
    • http://ramenhajimetustin.com/uploads/files/nivajif.pdfIn PDF document text
    • http://aven.su/userfiles/file/10687279689.pdfIn PDF document text
    • http://eluvial.com/sites/all/sites/eluvial.com/files/fegojibuvezejunezaz.pdfIn PDF document text
    • http://restravel.ru/ckfinder/userfiles/files/begoniwuwivi.pdfIn 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://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_off00010b6e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10B6E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00012380.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12380 19568 bytes
SHA-256: 2233bae67804c8446fac43eb3126f1a02f1162a1f19eef035348268196290f9e
font_02_sfnt_off000156c8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x156C8 10600 bytes
SHA-256: 27959a7c47d240008e12a6655af3537b71485f7734719b90397582136d11a73e