Malicious PDF — malware analysis report

Static analysis result for SHA-256 810a3b962b594f96…

MALICIOUS

PDF

80.0 KB Created: 2021-07-02 05:10:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 25140c889524293188f5a2f5e8b3ac51 SHA-1: 7cadea3a25e4429b55f2bb2c3fda154e98bbd61f SHA-256: 810a3b962b594f96b0f4379a453e8aa497d192046ed92d80480203b722f22daf
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains numerous external URIs and links to compromised WordPress uploads, indicating it functions as a link farm. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or distributing further malware. No scripts were extracted, but the structure and URLs point towards a malicious document designed to lure users to external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

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://coretry.ru/uplcv?utm_term=knee+joint+is+an+example+of
    • http://www.tsssport.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609e49bc4bac8---39296086379.pdf
    • https://faceless.me/userfiles/files/zetudiguwa.pdf
    • http://www.pirac.org/wp-content/plugins/super-forms/uploads/php/files/30948aa2fb06c57e1482882bc5af8ddb/49117127981.pdf
    • https://rlvanstory.com/wp-content/plugins/super-forms/uploads/php/files/dca46bbae84f7a6b53f65314a6de8355/kaxofopaxuvu.pdf
    • https://www.formwork.co.uk/wp-content/plugins/super-forms/uploads/php/files/onpf11k4u3n6b5cgt3fnh0no2t/zipajuvewevuvebaxokuro.pdf
    • https://dentinale.eu/wp-content/plugins/super-forms/uploads/php/files/bf55e4c645e0f6c9f70452d84a4a9de7/57813047411.pdf
    • https://cwlighting.com/wp-content/plugins/super-forms/uploads/php/files/57c32b8ea522a9616e7836e82364f757/2117095776.pdf
    • https://www.scanworld.se/wp-content/plugins/formcraft/file-upload/server/content/files/1607c54d3b51ac---gigogavizozaxa.pdf
    • https://arenda1s.ru/wp-content/plugins/super-forms/uploads/php/files/2a3347904be7ba272ecba100a85d7390/64134906411.pdf
    • http://intechsol.kz/wp-content/plugins/formcraft/file-upload/server/content/files/160c674fa66688---gewujafuma.pdf
    • http://aiswaryamatrimonials.com/fck_uploads/file/nifazopurijuvovaka.pdf
    • http://in-dapt.com/wp-content/plugins/formcraft/file-upload/server/content/files/160943e67cd0f4---68848431537.pdf
    • http://accessibilite-salle-eau.com/ckfinder/userfiles/files/69712149731.pdf
    • http://mariopresto.pl/userfiles/file/7586886429.pdf
    • http://itkaufmann.com/images/fckimages/file/13256483036.pdf
    • http://kaplanpm.com/wp-content/plugins/formcraft/file-upload/server/content/files/16094c9d8dc70f---setajanikoribabovaseg.pdf
    • https://www.qlsny.com/wp-content/plugins/super-forms/uploads/php/files/9a0c48994bbb978d1b8dfab4c97c5585/dafibulanapaja.pdf
    • http://wypelnienia.kratex.pl/wp-content/plugins/super-forms/uploads/php/files/2ac40c24d96ba1ce7f942879e50e0200/ruxedimatajemetenagixuma.pdf
    • https://robinio.de/wp-content/plugins/super-forms/uploads/php/files/ug4uktujdd00f746hrf5rctb9g/47367369001.pdf
    • https://pensiuneavlasin.ro/wp-content/plugins/super-forms/uploads/php/files/f9694vmmo88nmb9vdptgfkultb/1168016284.pdf
    • https://unibel.pl/pliki/upload/file/famasutesove.pdf
    • https://oversaslogistica.it/file/90472132390.pdf
    • https://dungcuruamui.com/wp-content/plugins/super-forms/uploads/php/files/5mvea9k3m9hkap6b3232bnvn21/virabekiwav.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d829.bin
a2c7d66f2972bafa5c73a77620eb6c71d298d36cb7ca131169fa015e4531c17d
pdf-font-stream PDF embedded font (sfnt) at offset 0xD829 16372 bytes
font_01_sfnt_off0001029e.bin
15dcfcf9b37542ebf21d6b9ddabd29f38bc214b26aa3654246f7cbd5e5d38426
pdf-font-stream PDF embedded font (sfnt) at offset 0x1029E 10644 bytes
font_02_sfnt_off00011afa.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11AFA 16792 bytes