Malicious PDF — malware analysis report

Static analysis result for SHA-256 b5bd585e5b505f19…

MALICIOUS

PDF

76.2 KB Created: 2021-06-11 10:09:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-02
MD5: 4f4fef27f6775d820383459c894e2622 SHA-1: 8958655d9c89971c916741156860f8773d6f65f8 SHA-256: b5bd585e5b505f19db9a2b77add473fd99bf32e0d1e04cb4fb2dc7bcdfbd0e61
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9949

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
  • PDF differential parser failed info PDF_DIFFERENTIAL_PARSE_FAILED
    The cross-check parser (pdfminer.six) failed on this file: PDF differential parser failed: PDFSyntaxError. Static heuristics still ran and any of their findings above are valid; only the differential cross-check signal is missing.
  • 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://synerhu.ru/uplcv?utm_term=demon+slayer+manga+chapter+183 PDF link annotation
    • http://www.leesii.com/wp-content/plugins/formcraft/file-upload/server/content/files/160707d39761bc---3343842661.pdfIn PDF document text
    • https://pyhm.ca/wp-content/plugins/super-forms/uploads/php/files/7hoaalgaj562f2fvh5j69c4h6k/zexixofezejoviguxixami.pdfIn PDF document text
    • http://aeskulap24h.com/wp-content/plugins/formcraft/file-upload/server/content/files/16090d4da82ba8---34867767803.pdfIn PDF document text
    • https://adbetelparaguay.com/wp-content/plugins/super-forms/uploads/php/files/f6b9cc624824430ad9f71c9a78505e56/22409699712.pdfIn PDF document text
    • http://discoveryenglish.org/wp-content/plugins/formcraft/file-upload/server/content/files/1607f980fd9610---26821941201.pdfIn PDF document text
    • https://joyfool.art/wp-content/plugins/super-forms/uploads/php/files/fd134e9d1c294e87625aa488808747be/feziz.pdfIn PDF document text
    • http://cetinelektrik.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1609fccbd2882f---52903435402.pdfIn PDF document text
    • http://www.christinemartin.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16099c740863d2---27232132951.pdfIn PDF document text
    • http://meble-tk.pl/userfiles/file/visekodetadul.pdfIn PDF document text
    • https://k-kompany.ru/wp-content/plugins/super-forms/uploads/php/files/764bcd01341d23eedf28922cd6c13420/vabusogatitipafazixas.pdfIn PDF document text
    • http://www.dadosefatos.net.br/wp-content/plugins/formcraft/file-upload/server/content/files/160763e1d1c9ac---62613244668.pdfIn PDF document text
    • https://akamercedes.com/images/uploads/files/50149899593.pdfIn PDF document text
    • https://sancarspune.com/wp-content/plugins/super-forms/uploads/php/files/4c2f3e3dd2d4be5128168186a91f7d0c/vujunub.pdfIn PDF document text
    • http://www.emailposte.com/pictures/91208593871.pdfIn PDF document text
    • https://kuechentreff-schmid.de/wp-content/plugins/super-forms/uploads/php/files/mu1trkdfe1tr11vo4266pjt9g9/51817845131.pdfIn PDF document text
    • https://www.msolartop.cz/wp-content/plugins/formcraft/file-upload/server/content/files/160a32e1d07052---53274654791.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://scripts.sil.org/OFLIn PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d6e4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD6E4 4148 bytes
SHA-256: 6a75cf9eef4b97dd76ae7a2799fc1af94cec246860591e44af7880b82856f788
font_01_sfnt_off0000e592.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE592 5856 bytes
SHA-256: f63c9d6decfd9238ab113309cc485661c247cbe18da811f611ffc9514f8b10e5
font_02_sfnt_off0000f970.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF970 10156 bytes
SHA-256: 8e2c35475bbd231fe870a66c45c137cb89e062464044b85d961a8cc57cdbe458
font_03_sfnt_off00011c2f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11C2F 16156 bytes
SHA-256: 70692197411a8c12d2c476469319b10f66dd0d34dfd14bcbbd550be5c659e77c