Malicious PDF — malware analysis report

Static analysis result for SHA-256 b5c00f1f944dc74e…

MALICIOUS

PDF

83.4 KB Created: 2021-08-18 17:31:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 7a66435770aed714f0473330ad6d7424 SHA-1: 37e294691f9044025435c870df8554e39bb6a441 SHA-256: b5c00f1f944dc74efe3c39886aff3a1ba8ce3a0241bb85457aaf01e477cfee6a
156 Risk Score

Malware Insights

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

The file is identified as malicious by ClamAV and an ML classifier. It contains numerous embedded URLs, many of which point to compromised WordPress sites or disposable hosting, indicating a link farm designed for SEO poisoning or phishing. The PDF structure and heuristic firings strongly suggest an attempt to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.8903

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
  • 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://jiptv.nl/wp-content/plugins/super-forms/uploads/php/files/qou91jk4pro03ko38dpqqecrp7/xunixapu.pdf
    • http://risme.vn/files/mojukagijesimirat.pdf
    • http://clinicacomciencia.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1609a2ec43bec4---wurebamekojam.pdf
    • https://klubkanine.com/home/klub/public_html/ckfinder/userfiles/files/83097022638.pdf
    • http://antik-cafe-bergen.de/wp-content/plugins/formcraft/file-upload/server/content/files/160ecab0ed593f---36361453576.pdf
    • http://nationshield.ae/userfiles/files/30049447745.pdf
    • https://udachi.co.th/wp-content/plugins/super-forms/uploads/php/files/n34bsdhr3108h94qpkgjp4q1h2/tamosutuwiteturexef.pdf
    • https://nhachoxebus.com/upload/fck/file/74374605538.pdf
    • http://getvisa.ru/images/File/ziluwinibixuziri.pdf
    • http://studiolaviano.it/userfiles/files/joradugofatinivagawozanu.pdf
    • https://www.alapan.org/fckimages/file/13397899317.pdf
    • https://quickonboarding.com/wp-content/plugins/super-forms/uploads/php/files/03815614c6d9c5c2677a93d33f9db648/49677407251.pdf
    • https://stgeorgedentalcare.in/ckfinder/userfiles/files/71990638931.pdf
    • https://garyjetcenter.com/wp-content/plugins/super-forms/uploads/php/files/f1f82042936736c004daa30f7d12f4c9/86935280926.pdf
    • http://www.empresshasnoclothes.com/siteuploads/editorimg/file/zigadexuduvevokofabiso.pdf
    • http://mcelvain2020reunion.com/clients/b/b5/b5167212b805812c9439186484f80f5e/File/sefafisetatutotak.pdf
    • http://csc0731.com/userfiles/file/20210801054847_2xk6y7.pdf
    • http://optimaglobal.net/ckupload/files/tidoxewusuzalalawibitun.pdf
    • http://www.auditsi.com/wp-content/plugins/formcraft/file-upload/server/content/files/16071557cf1dd9---22076532874.pdf
    • https://zippy-inc.com/app/webroot/userfiles/files/26125970587.pdf
    • https://inchiriereelicoptere.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160b5c6fbbed55---87978118567.pdf
    • http://cleannshieldflorida.com/wp-content/plugins/super-forms/uploads/php/files/cc1b6ab5955e9adf01e1421f63a78bf5/verabu.pdf
    • https://soba05.org/wp-content/plugins/super-forms/uploads/php/files/ec563bc247a8fd1a67ea5fd1c4c9ad46/37012885605.pdf
    • https://yidinfo.net/wp-content/plugins/super-forms/uploads/php/files/88dhjlpnusulka1g4g1itn1rpn/gumevofupuxinuvesosuwij.pdf
    • https://ikitellirezistans.com/upload/files/nugawumimawetixadufiko.pdf
    • https://asiaviews.org/wp-content/plugins/super-forms/uploads/php/files/60b1bti8rn31ehe1kvkihe92u5/pubuvo.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=ejercicios+de+calculo+mental+para+cuarto+grado+de+primaria+para+imprimir
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000eba7.bin
9c18616095e83b814479859b9ac4f142d171b818273134058062434426877bb4
pdf-font-stream PDF embedded font (sfnt) at offset 0xEBA7 17760 bytes
font_01_sfnt_off00011901.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11901 16792 bytes
font_02_sfnt_off00013118.bin
a076c9ce51536141d0428455db569a83f3cac0a70a354799e25c3d3bca07edd8
pdf-font-stream PDF embedded font (sfnt) at offset 0x13118 11068 bytes