Malicious PDF — malware analysis report

Static analysis result for SHA-256 6aff1d4a7c79d2fc…

MALICIOUS

PDF

73.0 KB Created: 2021-10-02 13:36:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: e682587412e7473e3ce064d47883ae20 SHA-1: 5d9e5fa76aa780b5bb83bc9bc0f32e2f1319cbe4 SHA-256: 6aff1d4a7c79d2fc9b9dfb6e5fcb0d9adab58f07668aeb6d9d9a5a18bac21bf2
156 Risk Score

Malware Insights

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

The PDF contains numerous links to external websites, many of which are hosted on disposable domains or compromised CMS upload directories, indicating a link farm designed to redirect users. The ClamAV detection and ML classifier strongly suggest malicious intent, likely for phishing or malware distribution. No scripts were extracted, and the document body was unreadable, but the heuristic firings clearly point to a malicious link aggregation strategy.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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://cuatro-pr.org/sites/default/files/file/mutufosujowubepesexim.pdf In PDF document text
    • http://urparitet.ru/admin/ckfinder/userfiles/files/40214953798.pdfIn PDF document text
    • https://nacituran.com/userfiles/file/bumaforipuzesovovisabe.pdfIn PDF document text
    • https://totalyoumovement.com/wp-content/plugins/formcraft/file-upload/server/content/files/16149c9a425f42---1942915642.pdfIn PDF document text
    • http://sklenicky-obchod.cz/web/admin/fckeditor/userfiles/file/67017584020.pdfIn PDF document text
    • https://poojaindiangrill.com/nbloom/fckuploads/file/wofanofokutumadozabufivid.pdfIn PDF document text
    • https://ecableapp.com/FCKeditor/FCKimgUpload/file/91322177816.pdfIn PDF document text
    • http://stellarp.com/userfiles/files/72078414797.pdfIn PDF document text
    • http://floridadressyourhome.com/uploaded_files/userfiles/files/29518286468.pdfIn PDF document text
    • http://isagenixmakessense.com/ckfinder/userfiles/files/doguresepeza.pdfIn PDF document text
    • http://tydafa.com/dafa/uploadfiles/20210917203830.pdfIn PDF document text
    • http://ytovietnam.net/ckfinder/userfiles/files/51190679345.pdfIn PDF document text
    • http://zespolbahamas.pl/zdjecia/file/viguzonito.pdfIn PDF document text
    • https://nhatthiengroup.com/files/uploaded/files/viwogipejufos.pdfIn PDF document text
    • http://h-n-s.net/userfiles/file/86049658377.pdfIn PDF document text
    • http://euro-ex.net/images/blog/file/zogutedejenesevugubora.pdfIn PDF document text
    • http://phone-server.com/userfiles/file/kobujaweberuno.pdfIn PDF document text
    • https://pchome.uzai.ca/upload/files/vufukizitoxe.pdfIn PDF document text
    • http://orderbestwings.com/uploads/files/penubipusepeg.pdfIn PDF document text
    • http://abovomedia.hu/_user/file/zakajomipawenunara.pdfIn PDF document text
    • http://nuyewrecruitment.com/wp-content/plugins/super-forms/uploads/php/files/7dc39d6f5979085f5faa86a728c35523/pinuzolafijasu.pdfIn PDF document text
    • https://parlagame.com/calisma2/files/uploads/pukisawiz.pdfIn PDF document text
    • http://xn--c1adbeke4asdefy.xn--p1ai/ckfinder/userfiles/files/17774944924.pdfIn PDF document text
    • https://travelsafeway.com/userfiles/file/32968057145.pdfIn PDF document text
    • https://voicelux.ru/wp-content/plugins/super-forms/uploads/php/files/dd59a9ca2f9707abd9387b7a48660c2f/60950598631.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1xuhb7AK25c/uplcv?utm_term=benefits+of+breastfeeding+for+babyPDF 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_off0000b8c8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB8C8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d0da.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD0DA 17496 bytes
SHA-256: 6990550ab7ebfb5bf75a4094df1e4647bf390595568696409eaea693165c7ffb
font_02_sfnt_off0000fdd9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFDD9 10792 bytes
SHA-256: ff8d8a94af4ca2b8a51f541742677ae85b01bc0ad0d12cb4addd88612be6632f