Malicious PDF — malware analysis report

Static analysis result for SHA-256 8d535ef934875d19…

MALICIOUS

PDF

70.6 KB Created: 2021-09-03 12:59:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 505a91b47756599e8b330c086d1ced63 SHA-1: de29302330cf745198e2ff511bc6acb1405e76ee SHA-256: 8d535ef934875d197bf365e71ab5584926c0ee96f55d027bcb1da2e6a8b8b14f
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating it is likely a phishing or malware distribution lure. The document functions as a link farm, with numerous embedded URLs pointing to potentially compromised websites or disposable hosting. These links are designed to redirect users to malicious content, aligning with the characteristics of a phishing attack delivered via attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.6872

Heuristics 5

  • 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
  • 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://medvor.ru/uplcv?utm_term=exercicios+sobre+geradores+e+receptores+com+gabarito+pdf PDF link annotation
    • https://ebal.ro/app/webroot/files/userfiles/files/todepu.pdfIn PDF document text
    • https://www.denisonlandscaping.com/wp-content/plugins/formcraft/file-upload/server/content/files/160795cedd6f05---23842795600.pdfIn PDF document text
    • http://langeline.com/ckeditor/upload/files/fesazozutaset.pdfIn PDF document text
    • https://www.alpha-dynamics.gr/wp-content/plugins/formcraft/file-upload/server/content/files/16081199728076---70374975305.pdfIn PDF document text
    • https://canvasations.com/wp-content/plugins/super-forms/uploads/php/files/rhqmpekno8lhsf7eofefdo22d7/54760017797.pdfIn PDF document text
    • https://matras-matrasych96.ru/admin/ckfinder/userfiles/files/78216995108.pdfIn PDF document text
    • http://msinziniering.com/userfiles/file/pegisosopu.pdfIn PDF document text
    • https://www.heainc.com/wp-content/plugins/formcraft/file-upload/server/content/files/16073e578d7d1a---78941919105.pdfIn PDF document text
    • https://nhaban24h.com.vn/wp-content/plugins/super-forms/uploads/php/files/86ood7imse0qotfd4h1ieokde6/17043277586.pdfIn PDF document text
    • http://ned.ru/uploads/files/puxawozinefebofasodibuwo.pdfIn PDF document text
    • https://cdmsig.com/ckfinder/userfiles/files/deligexezesewularetu.pdfIn PDF document text
    • http://noospc.ru/SITE/files/editor/file/58327537115.pdfIn PDF document text
    • http://szao-spb.ru/images/news/file/vozatavurezobejaf.pdfIn PDF document text
    • http://raduzhniy.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d0a013ec336---niwefajokopokixuboremi.pdfIn PDF document text
    • http://getampedmag.com/ckfinder/userfiles/files/mefukupubonatit.pdfIn PDF document text
    • http://xn----7sbqwxdbhblh2h.xn--p1ai/data/file/dawabexakedixiwefafojumel.pdfIn PDF document text
    • http://jsdarvin.com/files/vepavozebaj.pdfIn PDF document text
    • http://www.goataxiservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609c870e83efe---16340150266.pdfIn PDF document text
    • http://limpiasol.com/wp-content/plugins/formcraft/file-upload/server/content/files/16106f74b159f0---tixujimaneduloz.pdfIn PDF document text
    • https://fptica.ru/images/file/13259429049.pdfIn PDF document text
    • http://ctkupavna.ru/upload/file/48695046854.pdfIn PDF document text
    • https://zoorichi.com/temp/fckeditor/file/notupibu.pdfIn PDF document text
    • https://cosalesrep.com/wp-content/plugins/super-forms/uploads/php/files/a83b55ac5cd644ffa00bac02b6f58ebb/8991265226.pdfIn PDF document text
    • https://study-go.info/wp-content/plugins/super-forms/uploads/php/files/9951c97eeae35dbe0fd7df4f7e54a13a/rurodapusuburit.pdfIn PDF document text
    • https://lakecountyoralsurgery.com/wp-content/plugins/formcraft/file-upload/server/content/files/160baafbb67bbb---jaziwa.pdfIn PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000de04.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE04 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f61b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF61B 11040 bytes
SHA-256: d5a4370be65ff51bce0359c24a5e9c6aed27884f8d13d3a1bf3a331cf3cc2184