Malicious PDF — malware analysis report

Static analysis result for SHA-256 4dd83600d6a0aba3…

MALICIOUS

PDF

74.9 KB Created: 2021-09-08 04:21:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 8d4703a22bee21b49085288ca98bca15 SHA-1: d8e07e552e3043e6c60f1e4e14cbcd74c054646a SHA-256: 4dd83600d6a0aba30d2ac7484d4de08965949a79e67b314a24d18c5a6f08fca7
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to compromised websites or disposable hosting, indicating a link farm designed to lure users to potentially malicious destinations. ClamAV and ML classifiers strongly indicate malicious intent, consistent with phishing or malware distribution tactics. The document body is heavily obfuscated and appears to be generated content rather than user-readable text.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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 http://www.laterveer-biesenbeek.nl/ckfinder/userfiles/files/16842787942.pdf In PDF document text
    • http://vudafrique.com/wp-content/plugins/super-forms/uploads/php/files/787518a4ab0f677b226812fe529137cf/serifugabasami.pdfIn PDF document text
    • http://onlinemidias.com/ckfinder/userfiles/files/gamesonuponojaxubazili.pdfIn PDF document text
    • http://juentai.com/userfiles/files/fipifaxowivu.pdfIn PDF document text
    • https://georeno.ca/userfiles/files/xogep.pdfIn PDF document text
    • http://vtdsbinhthuan.vn/public/uploads/userfiles/file/munokorevujumiderodazuk.pdfIn PDF document text
    • https://criteriacambio.com.br/wp-content/plugins/super-forms/uploads/php/files/qp4vkgs685fijt1ij8vq7k6tfb/nigilamux.pdfIn PDF document text
    • https://cdmsig1.com/ckfinder/userfiles/files/rexata.pdfIn PDF document text
    • http://aarogyamedico.com/userfiles/file/javetodus.pdfIn PDF document text
    • http://rld-carbon.ru/file/gizosafanubezem.pdfIn PDF document text
    • https://www.northamericatalk.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607a0b155b4a4---kupupufebonegikubixiwula.pdfIn PDF document text
    • https://sketchup360.vn/wp-content/plugins/super-forms/uploads/php/files/ori1rm2fcs7l0kedcnotb4l463/bigurunabesat.pdfIn PDF document text
    • http://www.iqubz.com/wp-content/plugins/formcraft/file-upload/server/content/files/160794eee24935---49651068366.pdfIn PDF document text
    • http://adamslakeband.org/userfiles/file/11337152742.pdfIn PDF document text
    • http://skuplaptop.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160b5c931105f0---83233235900.pdfIn PDF document text
    • https://walnutcreekguide.com/wysiwygfiles/file/232389365.pdfIn PDF document text
    • https://mebelpozakazu.ru/wp-content/plugins/super-forms/uploads/php/files/33215ae2339a3b1a4d22e835fde08bf9/xexolariwodozodarudefaf.pdfIn PDF document text
    • https://kompaspt1.com/contents//files/83299155231.pdfIn PDF document text
    • http://jjmcp.jp/userfiles/Image/file/mazadavu.pdfIn PDF document text
    • https://realimpacto.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1607eefae535de---54237399556.pdfIn PDF document text
    • http://seashoresilverlabradors.com/clients/4/48/482fd9669fb3260065120a60ccac5e48/File/bekusufufiwosisozabanij.pdfIn PDF document text
    • http://claudiodauelsberg.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160843e7f3b148---ximawasekutuwasud.pdfIn PDF document text
    • http://yachtandgulet.com/userfiles/file/vijavoxuzerisikanun.pdfIn PDF document text
    • https://seataclighting.com/wp-content/plugins/super-forms/uploads/php/files/de49c0792683f19948d30222e9b72e98/70476882670.pdfIn PDF document text
    • http://czdashan.cn/uploadfile/file/2021080907555673499.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/YTWXjIUwRh0/uplcv?utm_term=methods+of+arithmetic+mean+pdfPDF 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_off0000c3ce.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC3CE 16012 bytes
SHA-256: 8dc3e5f7e237288c498d695c28af76bd30c1cf6f4dcca9ea016ebcf3ba3d0102
font_01_sfnt_off0000ec8d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC8D 10832 bytes
SHA-256: c21a78eed19b08fabd2315269df5da87f1fa658a210129d98fbf1bf3fc7457dd
font_02_sfnt_off0001056b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1056B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1