Malicious PDF — malware analysis report

Static analysis result for SHA-256 25888d89f16d8a5b…

MALICIOUS

PDF

81.9 KB Created: 2021-09-19 13:16:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 019d6af9c8a02afac8f8a7e14e330970 SHA-1: d448a19036f9cb2290300d4c32213140f2e981b4 SHA-256: 25888d89f16d8a5bb5e58d0d9d986a2d17b0a060b9bca9d93b2d0620591ba2b1
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and a link farm pointing to compromised WordPress sites, suggesting an attempt to redirect users to malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. The primary attack vector appears to be a lure disguised as a software download link.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://laborke.ru/uplcv?utm_term=nokia+pc+suite+for+android+phone
    • http://www.luminicaambiental.com/wp-content/plugins/formcraft/file-upload/server/content/files/161422c8519f90---15763149993.pdf
    • https://dobre-akce.cz/media/files/file/26322247186.pdf
    • http://coquicart.com/ckeditor/ckfinder/core/connector/php/uploads/files/zovimegoj.pdf
    • http://badaranquehablar.com/userfiles/files/35547102220.pdf
    • http://www.vitrierbxl.be/wp-content/plugins/formcraft/file-upload/server/content/files/16137b1a7f1b82---62351112245.pdf
    • https://essuances.com/ckfinder/userfiles/files/zovomararenepufofana.pdf
    • http://studiotecnicopinto.it/userfiles/files/50366633504.pdf
    • http://agnieszkapawlik.com/userfiles/file/suwipefojovolaxo.pdf
    • http://incomingmakedonia.com/files/files/48806230521.pdf
    • http://belgium-ex.com/images/blog/file/gidatavon.pdf
    • http://wimborst-ceramics.nl/public/view/upload/fckeditor_images/file/puxiviwitasulabolodim.pdf
    • http://ylplj.com/ckfinder/userfiles/files/vopopakobokexireleferafa.pdf
    • http://agt.es/files/galeria2/files/laxevub.pdf
    • http://machi-tomo.xyz/js/ckfinder/userfiles/files/xiluzexuw.pdf
    • http://tsuiteru66.com/userfiles/file/wilakevizefox.pdf
    • http://bobas24.pl/Upload/file/suxasowolezo.pdf
    • http://regimhotelierbucuresti.com/images/userfiles/95721098615.pdf
    • https://die-elke.de/cms/elke_page_files/file/zojaxixaw.pdf
    • https://suadienlanhhanoi.net/upload/files/zogomaruvemobevojewuvi.pdf
    • http://goldsunjsc.com/upload/files/6252709678.pdf
    • https://zevkotodoseme.com/upload/ckfinder/files/12523494990.pdf
    • https://knurussian.kr/DATA/upload/files/202109051233505664.pdf
    • http://www.thelawchamber.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613eb1ac555b3---74679505002.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_off0000d9fb.bin
51a9391250ba04e5c7d030540e1c6c6de69e1cd63da98046ed3903666fd14a58
pdf-font-stream PDF embedded font (sfnt) at offset 0xD9FB 18124 bytes
font_01_sfnt_off000108c9.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x108C9 16792 bytes
font_02_sfnt_off000120e0.bin
bdd84c245cea361e88e7a63690cd74b4e237e058347dc2d416f32cb095a8b7af
pdf-font-stream PDF embedded font (sfnt) at offset 0x120E0 10840 bytes