Malicious PDF — malware analysis report

Static analysis result for SHA-256 dc8620ad2eb5e4d4…

MALICIOUS

PDF

70.9 KB Created: 2021-09-25 05:11:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 66c81c576eb034ed9482e5102985c18b SHA-1: 9a6871ad43dd528adfbacd4e95737acfd75295b4 SHA-256: dc8620ad2eb5e4d4bec0e5de48885b82de3b4d50afb8f1c30e4a60bc5c0593ed
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was detected as malicious by ML classifiers and ClamAV, indicating a phishing or trojan threat. It contains numerous embedded URLs, many pointing to compromised WordPress sites or disposable hosting, suggesting a link farm designed to redirect users to malicious content. The presence of these links and the overall structure strongly indicate an attempt to lure users to external, potentially harmful, websites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9916

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://senfina.top/uploads/files/56186261201.pdf In PDF document text
    • http://jawarakreasi.com/file/222566090.pdfIn PDF document text
    • http://polipadel.com/userfiles/file/27589685751.pdfIn PDF document text
    • https://sharmtocairo.com/userfiles/files/77767213392.pdfIn PDF document text
    • https://crmsaas.dswip.com/ci/userfiles/files/28251695676.pdfIn PDF document text
    • http://sporteambiente.it/ckfinder/userfiles/files/92216887723.pdfIn PDF document text
    • http://www.dnevi-sekretarjev.eu/wp-content/plugins/formcraft/file-upload/server/content/files/16136bebc139d9---bekimoguwubedebe.pdfIn PDF document text
    • https://www.cocochan.com.pk/wp-content/plugins/super-forms/uploads/php/files/afaf4726d29c73e46157768659537f52/nilewuvop.pdfIn PDF document text
    • http://cplust.com/upload/serback/files/20210924235425.pdfIn PDF document text
    • http://vncdata.net/app/webroot/uploads/files/42583603175.pdfIn PDF document text
    • http://universalthailand.com/images/uploads/ckfinder/files/sejeda.pdfIn PDF document text
    • http://www.risingstars.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/16144892f6d0f0---jebufegolefik.pdfIn PDF document text
    • http://forma8.kz/ckfinder/userfiles/files/bugejemarazi.pdfIn PDF document text
    • http://ricarda-allegra.de/userfiles/file/mijonumizomegufunaz.pdfIn PDF document text
    • http://zadonskiy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1613bd7f3a1ddf---nivedagameg.pdfIn PDF document text
    • http://venkateshservices.com/uploads/pegudezelumenanasib.pdfIn PDF document text
    • http://dailythang.com/userfiles/files/26768919306.pdfIn PDF document text
    • http://2girlstrippin.com/wp-content/plugins/formcraft/file-upload/server/content/files/16145c730d64fc---43769857825.pdfIn PDF document text
    • https://lokmangal.co.in/wp-content/plugins/super-forms/uploads/php/files/1e9f792e567036c022d2d8bf5c068b61/55660100836.pdfIn PDF document text
    • http://tianlanlawyer.com/filespath/files/20210922013421.pdfIn PDF document text
    • https://camphacement.vn/upload/files/pevit.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/161434c508ddd4---78220333639.pdfIn PDF document text
    • https://muguet.fr/sites/default/files/file/xijaparibomeketurorevaz.pdfIn PDF document text
    • https://aslimitada.com/userfiles/file/10940874814.pdfIn PDF document text
    • http://bienchidan.org/uploads/files/54556452025.pdfIn PDF document text
    • https://xosobacninh.vn/webroot/img/files/60656693142.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1xuhb7AK25c/uplcv?utm_term=oil+painting+apkPDF 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_off0000b513.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB513 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000cd2a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCD2A 10024 bytes
SHA-256: 992703fc7bad20adec62165b6dbc9ef33d83e67505aacc91e613015842ecba39
font_02_sfnt_off0000e38e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE38E 16696 bytes
SHA-256: 01f5841392c54483fc8a9d59cbc1f3f9c15c3fc3c45cd69fe41a5b35bee9da27