Malicious PDF — malware analysis report

Static analysis result for SHA-256 d354d07c9ab3012b…

MALICIOUS

PDF

79.0 KB Created: 2021-08-27 18:16:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 50f3aa43e802db00b0359354ad6a3ceb SHA-1: b09f71e964677ddf0b24bd5a539a818d213ab808 SHA-256: d354d07c9ab3012be8846f474edc8a0fded4c23a5bbe84e9963c4a99985dfcef
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised CMS upload directories or disposable hosting, indicative of a link farm. The ML classifier and ClamAV detection strongly suggest malicious intent, likely to lure users to phishing sites or download further malware. No scripts were extracted, and the document body was unreadable, but the heuristic findings and URL analysis are sufficient to determine the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9952

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://bonpetsupply.com/wp-content/plugins/formcraft/file-upload/server/content/files/16072e4d17c886---jefonobi.pdf In PDF document text
    • https://loskutova.site/wp-content/plugins/super-forms/uploads/php/files/32a533421c0a8442d0832bd7b8d501c4/govatevu.pdfIn PDF document text
    • http://k1a.ru/images/files/file/86707827000.pdfIn PDF document text
    • http://www.linkkorea.co.kr/wp-content/plugins/formcraft/file-upload/server/content/files/160b2a6162908d---nujalizijumosuxasupedi.pdfIn PDF document text
    • http://agro-vostok.ru/userfiles/file/zukuxuboluvowofewodaxu.pdfIn PDF document text
    • http://aplus.to/userfiles/file/ravafijafa.pdfIn PDF document text
    • https://halkapsikoloji.com/userfiles/file/8991658848.pdfIn PDF document text
    • http://www.celso.org/download/42830190031.pdfIn PDF document text
    • https://nikoljski.com/ckfinder/userfiles/files/97031168786.pdfIn PDF document text
    • https://glycocalyx.nl/userfiles/image/file/lotelofolem.pdfIn PDF document text
    • https://www.mercato.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/16105a79d0e115---puvujudebaper.pdfIn PDF document text
    • http://aa-nusd.jp/vavazukigoduduwoli.pdfIn PDF document text
    • https://k-kompany.ru/wp-content/plugins/super-forms/uploads/php/files/6276d1afed41fa3a90e87487ec274427/gakelixi.pdfIn PDF document text
    • https://qeyeoptical.com/ckeditor/ckfinder/userfiles/files/72179880891.pdfIn PDF document text
    • http://israel-aliya.com/wp-content/plugins/super-forms/uploads/php/files/faa63f9094bbc60813f47d3127b58ef6/25084816505.pdfIn PDF document text
    • https://allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/3817363f243305abb5f85d5af13b0474/87947123376.pdfIn PDF document text
    • http://supermarketdv.ru/files/file/39314375403.pdfIn PDF document text
    • http://www.ags-sib.ru/ckfinder/userfiles/files/31417821787.pdfIn PDF document text
    • http://www.finanzanlagen-honorarberatung.de/wp-content/plugins/formcraft/file-upload/server/content/files/1608769d9b54ec---wobasuxofu.pdfIn PDF document text
    • https://plumcourse.com/wp-content/plugins/super-forms/uploads/php/files/95b2a00821ca558324311641d1993907/39109447730.pdfIn PDF document text
    • https://lorenzonimmigrationlaw.com/wp-content/plugins/formcraft/file-upload/server/content/files/16104051dd680f---wibiredilene.pdfIn PDF document text
    • https://www.idahomedia.com/wp-content/plugins/super-forms/uploads/php/files/7ba506c528e1136fca38605abf623cb2/32104136334.pdfIn PDF document text
    • https://doitsolutions.co/wp-content/plugins/super-forms/uploads/php/files/ff57bc4f5282f4cb8760dcf446cd2293/nozapiweruzezokuji.pdfIn PDF document text
    • http://www.kotolantopeni.cz/files/1602151605.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/fzgW7-mxBc0/uplcv?utm_term=sample+of+correlational+researchPDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#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_off0000d866.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD866 10820 bytes
SHA-256: f8ebecbd58460481bcdac1213ffeab82480c809bcf211f5e085b129df2db4875
font_01_sfnt_off0000f113.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF113 17144 bytes
SHA-256: e8dda4275a971623392c7c8c1939556506f6ab16ab7377e359ea8c5c76319e26
font_02_sfnt_off00011cd9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11CD9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1