Malicious PDF — malware analysis report

Static analysis result for SHA-256 ca90b1dfb05976ae…

MALICIOUS

PDF

71.3 KB Created: 2021-09-09 11:18:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-21
MD5: a85234e3b571572b5836a831ea72f53d SHA-1: 2d66c6ca2b6dd1f962a17ac2039a5a769dce6387 SHA-256: ca90b1dfb05976aeb86c3a3268199105d951097ad54b1ece665f37312e7bca59
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, with one heuristic specifically identifying it as a link farm on disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware delivery. While no scripts were directly extracted, the PDF structure and embedded URIs suggest an attempt to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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 http://slmj8.com/data/userfiles/files/netatufijalubufovemufil.pdf In PDF document text
    • http://piemonteforyou.it/userfiles/file/xuruk.pdfIn PDF document text
    • https://dursunguney.com/userfiles/files/25979690818.pdfIn PDF document text
    • http://abhinavabhishad.org/userfiles/file/vomeguvesukug.pdfIn PDF document text
    • http://incomingmakedonia.com/files/files/88053014764.pdfIn PDF document text
    • http://nepalbestcargo.com/userfiles/file/28786437277.pdfIn PDF document text
    • https://shoppingplanet.ro/ckfinder/userfiles/files/lovulo.pdfIn PDF document text
    • https://qfse.co/images/uploaded_files/ckfinder/files/1630988944_6669cd3d4c.pdfIn PDF document text
    • http://trovas.com/userimages/23393000837.pdfIn PDF document text
    • http://delfosventures.eu/userfiles/files/zajavutorada.pdfIn PDF document text
    • https://peoplesmodelinternational.com/ckfinder/userfiles/files/35146233627.pdfIn PDF document text
    • http://pusheng168.com/uploadfiles/20210906002539.pdfIn PDF document text
    • https://o-dance.com/upload/files/42645807533.pdfIn PDF document text
    • http://shacklefordlawoffice.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/jovuxefimubamopoles.pdfIn PDF document text
    • https://congchunghadong.com/uploads/files/fotiwu.pdfIn PDF document text
    • http://haki.vn/uploads/files/fuzowijonafako.pdfIn PDF document text
    • http://wdnederland.nl/file/53640169030.pdfIn PDF document text
    • http://spharma.ua/files/file/76878799340.pdfIn PDF document text
    • https://sausalito.com/wysiwygfiles/file/25282102493.pdfIn PDF document text
    • http://transcash.com/ci/userfiles/files/vubazulasereze.pdfIn PDF document text
    • https://ever-progress.dacola.com/upload/files/80334541522.pdfIn PDF document text
    • https://eltonltd.ru/sites/default/files/uploads/49602669563.pdfIn PDF document text
    • http://universalgroupautos.com/files/others/32138938510.pdfIn PDF document text
    • http://osmed.cz/app/webroot/files/files/97987735378.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/Om9ozkHLxGw/uplcv?utm_term=observation+in+research+pdfPDF 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_off0000b65a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB65A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ce6c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCE6C 15800 bytes
SHA-256: 3225a99e8225d977fde10d1d33f820d813619b509233e7461cd16eb8758074fe
font_02_sfnt_off0000f695.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF695 10904 bytes
SHA-256: b45444c6ed67dada8136cf3f226ab57f758b39a710bd436553690c193a4e3903