Malicious PDF — malware analysis report

Static analysis result for SHA-256 d815456218d0f837…

MALICIOUS

PDF

84.4 KB Created: 2021-09-04 09:08:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 7091cf7e18534647b9c1ce682089ec9e SHA-1: 9e3a3c2b6d9bcadac7a54d441bdd0edefe43d79d SHA-256: d815456218d0f837644e03299cba3c75b1e2a33aef2222d8d6d3701c53f60361
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics indicate the PDF contains a link farm pointing to compromised WordPress upload storage and disposable hosting, suggesting a phishing or SEO poisoning attack. The document body is unreadable, but the presence of numerous external URIs, many of which are unknown or point to potentially compromised sites, strongly supports the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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 http://mko-yug.ru/wp-content/plugins/super-forms/uploads/php/files/128ca5dff878a2445ed594e4a4e5722d/18040156494.pdf In PDF document text
    • http://www.mediacomriccione.it/wp-content/plugins/formcraft/file-upload/server/content/files/160ecb767afaae---95973617913.pdfIn PDF document text
    • http://arlingtonhigh1961.com/clients/e/ef/ef36f0800c0a5d5a0b00d5ecc8c3c6da/File/jusugesepufadowib.pdfIn PDF document text
    • http://antik-cafe-bergen.de/wp-content/plugins/formcraft/file-upload/server/content/files/160708ef153b8a---52779361090.pdfIn PDF document text
    • http://liburnia.pl/userfiles/file/22522457312.pdfIn PDF document text
    • https://taksis.lv/taksis/userfiles/file/27207696323.pdfIn PDF document text
    • http://baovephuongtroi.com/vietkiendo/upload/file/wuvepudajiru.pdfIn PDF document text
    • http://guowangcable.com/d/files/69484963877.pdfIn PDF document text
    • http://recrute.fr/files/files/23077188529.pdfIn PDF document text
    • http://moveisgarciadigital.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1607eebff6862a---6303498040.pdfIn PDF document text
    • https://madeinstlucia.com/userfiles/files/36906146561.pdfIn PDF document text
    • http://resetimpianti.it/reset/public/file/12144502672.pdfIn PDF document text
    • http://tokstar.com/_UploadFile/Images/file/96044988631.pdfIn PDF document text
    • https://accesoriosalmayor.com/images/userfiles/file/83621792331.pdfIn PDF document text
    • http://www.training4thefuture.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1607184852e31f---xewikilegenodonosud.pdfIn PDF document text
    • https://peltonfell.org.uk/ckfinder/userfiles/files/80375246634.pdfIn PDF document text
    • http://vina2002.com/uploads/files/8261888682.pdfIn PDF document text
    • http://beta-rc.com/upload/files/jumopetirijakudewusiparu.pdfIn PDF document text
    • https://rozgarnetwork.com/ckfinder/userfiles/files/22874388040.pdfIn PDF document text
    • https://aduanaldelvalle.com/userfiles/file/16884840585.pdfIn PDF document text
    • https://oneremote.ru/wp-content/plugins/super-forms/uploads/php/files/450eaac61b17d164f1d2d815e41e4769/tomevedonexep.pdfIn PDF document text
    • https://caraudioshop.ro/mm/file/natulilofutow.pdfIn PDF document text
    • http://www.radiopopiatej.com/wp-content/plugins/formcraft/file-upload/server/content/files/1611846a5099ad---16159190912.pdfIn PDF document text
    • http://kaiyudachem.com/filespath/files/20210822141232.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/LPIa9PGmDLg/uplcv?utm_term=les+vertus+du+gingembre+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_off0000e255.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE255 10776 bytes
SHA-256: 4dab04546ac615d306f6ce49b250c53b2b82d62594eac20ba3cc145012044341
font_01_sfnt_off0000faaa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFAAA 19568 bytes
SHA-256: f21cf84b3801a597c74143674ff5ed683d239fcb70b5d01ed0bd5381d644f922
font_02_sfnt_off00012bd3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12BD3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1