Malicious PDF — malware analysis report

Static analysis result for SHA-256 926c681600f1b071…

MALICIOUS

PDF

81.4 KB Created: 2021-08-30 15:56:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 2182df3756d0dd755d6f795bbe1684a0 SHA-1: 4a1cc6b1f88a6b77c06b8d351002c97867d546be SHA-256: 926c681600f1b071791ad154accb114bfc3523344105ce801e5bc26502ddf325
156 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to numerous websites, many of which are hosted on compromised WordPress installations or disposable domains. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The primary attack pattern involves luring users to external sites via a seemingly innocuous document.

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 https://bmw-zona.ru/uploads/file/5528852713.pdf In PDF document text
    • https://biogenetixpharma.com/ci/userfiles/files/12062243585.pdfIn PDF document text
    • http://veronicanealhome.com/wp-content/plugins/formcraft/file-upload/server/content/files/2/1607533da0a0f6---juxavikizimodipasilux.pdfIn PDF document text
    • http://www.hj-bouwt.be/wp-content/plugins/formcraft/file-upload/server/content/files/160890e0d05e77---lunibin.pdfIn PDF document text
    • http://jun-travel.com/userfiles/file/vuxibaxogujamotavud.pdfIn PDF document text
    • http://yakutiaprime.ru/SITE/files/editor/file/93805720415.pdfIn PDF document text
    • http://mdsalon.ru/img/lib/file/rozozuxexamefapurokadeze.pdfIn PDF document text
    • https://victory-agency.com/wp-content/plugins/formcraft/file-upload/server/content/files/16075eaa588cdb---pikisaguxamon.pdfIn PDF document text
    • https://www.chesapeake-lighting.com/wp-content/plugins/super-forms/uploads/php/files/65dd0b32497e0839450c6700dd0b51fc/39072809184.pdfIn PDF document text
    • http://thuonghieutoancau.vn/uploads/files/govotasanexoguvajuxibu.pdfIn PDF document text
    • http://www.putnamtaxi.net/wp-content/plugins/formcraft/file-upload/server/content/files/16098503906719---gufinaso.pdfIn PDF document text
    • http://rchs1964.com/clients/5/58/580abc73d3aac4ea3a2bdd7c75327783/File/ruzewej.pdfIn PDF document text
    • http://cec-intl.ru/app/webroot/files/file/62509591844.pdfIn PDF document text
    • http://seoulmenu.com/uploads/files/24826157986.pdfIn PDF document text
    • http://qytbearing.com/upfile/file/54708473775.pdfIn PDF document text
    • http://mp-hd.de/data/aktualnosci_imgs/file/podavusob.pdfIn PDF document text
    • http://bergfin.se/wp-content/plugins/formcraft/file-upload/server/content/files/16082b5a2c6256---fifimepipukazabibudepate.pdfIn PDF document text
    • http://amazingindiaphotos.com/amazingindiaphotos//upload/fckimage/file/38053588858.pdfIn PDF document text
    • https://mandalaconfeccao.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160aaf167da995---22888063857.pdfIn PDF document text
    • http://w-f-l.de/user_img/file/82903821409.pdfIn PDF document text
    • http://verynailscm.com/user_img/file/73338903314.pdfIn PDF document text
    • http://shreyaghoshal.com/konadnew/userfiles/file/mevesokilu.pdfIn PDF document text
    • http://forter.vn/hinhanh/file/jepokiwowal.pdfIn PDF document text
    • http://prinsart.ro/uploads/files/logesukup.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BvfzZFkJO3s/uplcv?utm_term=correct+order+of+narnia+booksPDF 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_off0000dbdf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDBDF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f3f1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF3F1 16844 bytes
SHA-256: e02115b98ff2cb331155b908404366fed6e6d087cb05bbf2d1e3ab97a024b6ea
font_02_sfnt_off00011eff.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11EFF 10688 bytes
SHA-256: d5343563c4cab26f49ec079f7322b28c17a4318f5fe1f1d63a623c76f9154b89