Malicious PDF — malware analysis report

Static analysis result for SHA-256 dc9f6c35ecf25779…

MALICIOUS

PDF

78.3 KB Created: 2021-09-23 00:35:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: c7d528af96cb3ef610742662a388ec2c SHA-1: 3e1967be5756b56a07106ebbb384160d2b344c60 SHA-256: dc9f6c35ecf2577939d1777b7762459778a7f40ed29b1b37aebe3c983ec09539
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to disposable hosting or compromised CMS uploads, indicative of a link farm designed to distribute malicious content or phish users. The ClamAV detection and ML classifier strongly suggest malicious intent, likely related to phishing or malware delivery. No scripts were extracted, but the embedded URLs and link farm structure are sufficient evidence of malicious activity.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9949

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://vitanov.rs/files/35612367485.pdf In PDF document text
    • http://vucert.vn/uploads/files/xajizogogetemuropogasowat.pdfIn PDF document text
    • http://knuhpharm.kr/userfiles/file/20210922054449.pdfIn PDF document text
    • http://alltechsro.cz/files/70527653507.pdfIn PDF document text
    • http://collectifff.be/imgdb/accueil/files/jisugipon.pdfIn PDF document text
    • http://ourdesign.hk/ckfinder/userfiles/files/wedamuxajaraxineno.pdfIn PDF document text
    • http://christmaslandint.com/userfiles/kokifavipanuvunanojig.pdfIn PDF document text
    • https://www.avenueroadadvertising.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614b9a195894f---68068399705.pdfIn PDF document text
    • http://www.novosib-sport.ru/ckfinder/userfiles/files/59044996389.pdfIn PDF document text
    • http://laibros.com/ckeditor/userfiles/files/turikirisanivowuregiv.pdfIn PDF document text
    • https://mamadona.ru/ckfinder/userfiles/files/40479087141.pdfIn PDF document text
    • http://zagazzo.com/userfiles/file/81180828335.pdfIn PDF document text
    • https://kingwrapcarspa.com/upload/files/botufixeleneneniguro.pdfIn PDF document text
    • http://strechybenesov.cz/content/6300526639.pdfIn PDF document text
    • https://gmonlinestore.com/wp-content/plugins/formcraft/file-upload/server/content/files/16142ab7dd82bd---wutonojuralisokuzi.pdfIn PDF document text
    • http://wizclub.net/upload/userfiles/file/xugipavirasazofubudomipop.pdfIn PDF document text
    • https://shiokuda2.com/contents/files/gatezufuzikad.pdfIn PDF document text
    • http://sacmacbook.net/userfiles/file/jabobixut.pdfIn PDF document text
    • https://123kozijnofferte.nl/wp-content/plugins/super-forms/uploads/php/files/5acd7df7b5d1d649ce875fa737364ff6/50027668896.pdfIn PDF document text
    • https://husvagnsexpo.se/wp-content/plugins/formcraft/file-upload/server/content/files/16135ac0d78da4---345860021.pdfIn PDF document text
    • http://gioiacompany.net/images/upload/file/baraluful.pdfIn PDF document text
    • http://sns-russia.ru/userfiles/file/39338305828.pdfIn PDF document text
    • http://chickendaylacrescenta.com/uploads/files/81383411249.pdfIn PDF document text
    • https://riondene.ch/img/uploads/file/jijemelujegamusigulobano.pdfIn PDF document text
    • http://di-tech.kr/fckeditor/userfiles/file/fulodok.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1xuhb7AK25c/uplcv?utm_term=beetv+apk+no+adsPDF 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_off0000cf21.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCF21 17228 bytes
SHA-256: ee5348b21c54c41700a6ac522dbdccec48dd28d12a35d5ff90d3823e8dc87166
font_01_sfnt_off0000fc1b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFC1B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011432.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11432 10356 bytes
SHA-256: 8aeca83913f8dbe95811670ac2443d8acc3c269d21dd0e6cef7207b9cee7f142