Malicious PDF — malware analysis report

Static analysis result for SHA-256 8cea181d3d3851d2…

MALICIOUS

PDF

86.0 KB Created: 2021-09-05 01:51:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 3301f23f383d5059e2a4e81194d25b48 SHA-1: 79deeccea9780bef0fc3d6e643709699a27fb532 SHA-256: 8cea181d3d3851d233c1d2ee91e6a08f32b276f4c96b564fc636485adbf7329f
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is identified as malicious by ClamAV and an ML classifier. It contains numerous URLs pointing to compromised WordPress sites and other domains, suggesting a link farm designed to redirect users to malicious content. The PDF structure and embedded URLs indicate a phishing or malware distribution attempt, likely delivered as a spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9848

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://outsourcedbackoffice.co.uk/wp-content/plugins/super-forms/uploads/php/files/2d94da3c211e5a8b65e09eec48c8a6e1/52069448191.pdf In PDF document text
    • https://encouragingmath.com/wp-content/plugins/super-forms/uploads/php/files/31676506841d78e00b8626ef18a17326/47063779354.pdfIn PDF document text
    • https://atlastoursntravels.com/userfiles/file/52388857475.pdfIn PDF document text
    • http://www.benvenutialmare.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c0d412cc906---43971258506.pdfIn PDF document text
    • https://lapalettedesarts.fr/gestion/file/81702873909.pdfIn PDF document text
    • https://vijyaiprismcrm.com/userfiles/files/bufin.pdfIn PDF document text
    • http://enidental.com/userfiles/file/20210730072147.pdfIn PDF document text
    • http://kasargod.net/uploads/file/niworemepaverevuserap.pdfIn PDF document text
    • https://www.heainc.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d1c3586d53e---52548895515.pdfIn PDF document text
    • https://jiu-hang.com/upfiles/editor/files/vofotebodewejagape.pdfIn PDF document text
    • http://stsaischoolamritsar.com/slbdavbatala/userfiles/file/11716450559.pdfIn PDF document text
    • https://tecsal.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1606cf3c81d56c---60598508907.pdfIn PDF document text
    • http://www.circoloaletrium.it/wp-content/plugins/formcraft/file-upload/server/content/files/160749fa2dac6a---73997417594.pdfIn PDF document text
    • https://www.hauptsache.cc/wp-content/plugins/formcraft/file-upload/server/content/files/16070df3792741---73383636905.pdfIn PDF document text
    • https://sckstone.com/wp-content/plugins/super-forms/uploads/php/files/34b3aef37aaaff6077cc0386cbaa71f6/85237907036.pdfIn PDF document text
    • http://bibrka-school.org.ua/ckfinder/userfiles/files/bogil.pdfIn PDF document text
    • https://bdata.vn/upload/files/54745115465.pdfIn PDF document text
    • http://mamam.by/upload/File/file/nudebi.pdfIn PDF document text
    • http://avtrak.ru/ckfinder/userfiles/files/4715905288.pdfIn PDF document text
    • https://victory-agency.com/wp-content/plugins/formcraft/file-upload/server/content/files/1611dc5fc973e4---roxoxugozages.pdfIn PDF document text
    • http://www.niziointerior.pl/upload/file/6037200105.pdfIn PDF document text
    • http://www.trotasierra.com/plugins/ckfinder/userfiles/files/duruwujakobu.pdfIn PDF document text
    • http://www.celso.org/download/pazujure.pdfIn PDF document text
    • https://sjalikave.hu/pictures/file/fuvefo.pdfIn PDF document text
    • https://torbay.ru/images/uploads/file/47404315316.pdfIn PDF document text
    • http://host.keraladreamhomes.com/~viswabrahmathach/admin/fckeditor/editor/filemanager/connectors/php/userfiles/file/kimivinawozipurenoletonew.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/YTWXjIUwRh0/uplcv?utm_term=pdf+annotation+app+ipadPDF 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_off0000ee58.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE58 10044 bytes
SHA-256: 5b42bbddb9cb3eaa5fd711d5a90751f02ff0f369eb6fcf34475475215af7cf1c
font_01_sfnt_off000104bb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x104BB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011ccd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11CCD 18044 bytes
SHA-256: 4cddbc0497c27b0c85eaecb46926825930e4bfd8b0b4e47b3cf3edc600553429