Malicious PDF — malware analysis report

Static analysis result for SHA-256 f592dc7209d27d54…

MALICIOUS

PDF

82.1 KB Created: 2021-09-20 16:44:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 465f45eaedf3fafa56cc65d6d99643e5 SHA-1: b982c2e8bee6b4fc110eae94f515601f3f7a3cb4 SHA-256: f592dc7209d27d541bfb1580a28793c3d7d111d5f2c59b6a7b68c18424a39eca
146 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs pointing to disposable domains, characteristic of a link farm designed to obscure malicious destinations. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' directly supports this assessment. While no scripts were explicitly extracted, the malformed stream length and ML classifier indicate active content, likely JavaScript, used to facilitate redirection to these URLs.

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
  • Malformed active-content stream length medium PDF_MALFORMED_EXPLOIT_STREAM_LENGTH
    A PDF stream that carries active/exploit-looking content has a declared /Length that does not match the recovered stream body. Malformed stream boundaries and length mismatches are common parser-evasion/supporting evidence around Reader exploit streams.
  • 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://krisoc.ru/uplcv?utm_term=yu+gi+oh+online+hack PDF link annotation
    • https://dursunguney.com/userfiles/files/rubuselepowoxokase.pdfIn PDF document text
    • https://kapefashion.com/files/files/lezadimibid.pdfIn PDF document text
    • http://thetestmag.com/userfiles/files/32218105463.pdfIn PDF document text
    • http://candientuvibra.com/images/file/32657075865.pdfIn PDF document text
    • http://lalitas-thaimassage-spa.de/wp-content/plugins/formcraft/file-upload/server/content/files/16141051fe9261---656459819.pdfIn PDF document text
    • http://netdepphunu.vn/images/userfiles/file/14586192218.pdfIn PDF document text
    • http://ocvitlucky.com/vietkiendo/upload/file/37072585681.pdfIn PDF document text
    • http://sushimura1.com/uploads/files/29482050302.pdfIn PDF document text
    • http://karpatskiles.ru/store/file/51993697365.pdfIn PDF document text
    • http://futboltotal.net/images/files/97529652012.pdfIn PDF document text
    • http://www.pattyn360.com/upload/forum/files/64586632458.pdfIn PDF document text
    • http://shoreluxurylimos.com/userfiles/files/52573503528.pdfIn PDF document text
    • http://mimarathi.live/assets/ckfinder/core/connector/php/uploads/files/batir.pdfIn PDF document text
    • http://thienminhgroup.com/uploads/userfiles/file/wikudidife.pdfIn PDF document text
    • https://realwebguys.com/wp-content/plugins/formcraft/file-upload/server/content/files/16137936b7c171---vorojilobizovapesab.pdfIn PDF document text
    • https://imotrading.com/images/userfiles/mojewi.pdfIn PDF document text
    • https://pinpointfeedtech.com/ckfinder/userfiles/files/sikozorojireguv.pdfIn PDF document text
    • http://mlsy.cz/images/file/files/purelivus.pdfIn PDF document text
    • https://hardlineconstruct.ro/app/webroot/files/userfiles/files/ganov.pdfIn PDF document text
    • https://ahl2005.com/ckfinder/userfiles/files/18637249701.pdfIn PDF document text
    • https://goodmix-psc.com/userfiles/files/97709571101.pdfIn PDF document text
    • https://groupekheidri.com/ckfinder/userfiles/files/guzedigodumun.pdfIn PDF document text
    • http://www.fashiongale.ro/userfiles/files/59828599815.pdfIn PDF document text
    • http://kaupa.cz/userfiles/file/sakegukufabexudiwasetugu.pdfIn PDF document text
    • 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_off0000dcd5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDCD5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f4e7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF4E7 17776 bytes
SHA-256: 02844bed33701ad170c45756f210ac870d860a9f839d85e44139184fbd048332
font_02_sfnt_off00012377.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12377 10320 bytes
SHA-256: d4076a22562b3af84bc880c10f193c6ea4308ec87667461198f77bec6521a26f