Malicious PDF — malware analysis report

Static analysis result for SHA-256 ecdc5b34dc94b8f4…

MALICIOUS

PDF

106.8 KB Created: 2021-07-03 01:07:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 3d5eb03cf35b27e51ecd58e7faf433cb SHA-1: 9d20a891da3e4e09b6cb8b3ed53a2095de209201 SHA-256: ecdc5b34dc94b8f4488a7dcfdb3d194f1e37e8d71b72ad9b6ada7e025c52fa9c
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF was flagged by ClamAV as Pdf.Phishing.Trojan and a machine learning classifier indicated a high probability of maliciousness. It contains numerous links, many pointing to compromised CMS uploads and disposable hosting, suggesting a link farm designed to redirect users. The presence of external URIs and the overall structure indicate an attempt to lead users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9935

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
  • 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://www.isnb.co.uk/wp-content/plugins/super-forms/uploads/php/files/b3601d1cee65e74071b55a5f967bf5fc/rokuwidixolofot.pdf In PDF document text
    • http://nowator-zpu.pl/userfiles/file/gemegaxamepuxumog.pdfIn PDF document text
    • http://nek.ua/wp-content/plugins/formcraft/file-upload/server/content/files/160c01d3fd32b7---vabosodexuwuxozuf.pdfIn PDF document text
    • http://fashioncenterpoint.com/wp-content/plugins/super-forms/uploads/php/files/aeaaef01606a3f7a10ae01462e7728d3/tovapozav.pdfIn PDF document text
    • https://www.advids.co/wp-content/plugins/formcraft/file-upload/server/content/files/160849459ef60e---sibazuvaperudezebavej.pdfIn PDF document text
    • https://archcosmeticstudio.com.au/wp-content/plugins/super-forms/uploads/php/files/8a85f146995cdbbaf3023a8e7864f7c7/21790847378.pdfIn PDF document text
    • http://blog.crowdly.com/wp-content/plugins/formcraft/file-upload/server/content/files/16079a693a570c---50826201922.pdfIn PDF document text
    • http://www.deadclan.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160b58fa2d4b78---madapawe.pdfIn PDF document text
    • https://alphaveneers.co.uk/wp-content/plugins/super-forms/uploads/php/files/c0384de2e91e7c3bcff230b2af412ff4/fixegimu.pdfIn PDF document text
    • https://encouragingmath.com/wp-content/plugins/super-forms/uploads/php/files/f71df57b2123d923efeb262a931b4ca9/naneg.pdfIn PDF document text
    • http://nutronicltd.com/userfiles/file/9602675691.pdfIn PDF document text
    • http://emke.hu/uploads/ckfinder/userfiles/files/tajamev.pdfIn PDF document text
    • https://www.hamburgeriaagricola.com/wp-content/plugins/super-forms/uploads/php/files/hc4n61bqk2u0lgvi4pav1j3sjn/pavalakexofiki.pdfIn PDF document text
    • https://quangcaowebsite.vn/uploads/files/55181032139.pdfIn PDF document text
    • https://www.vigo.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160b7d6cf0668f---71421096567.pdfIn PDF document text
    • https://vmkstroi.ru/wp-content/plugins/super-forms/uploads/php/files/b15e27ebe7115b0e0c2d0b9f676a7ff0/julabefupivoworuxol.pdfIn PDF document text
    • https://www.chesapeake-lighting.com/wp-content/plugins/super-forms/uploads/php/files/3fde5842a0e85d6e4e5024512c7ae362/bepafitomijowiz.pdfIn PDF document text
    • http://poltinka.ru/userfiles/file/66014568832.pdfIn PDF document text
    • http://beijingxinzhi.com/userfiles/file/20210613113800_843194797.pdfIn PDF document text
    • https://p99.tw/pro_pic/files/vepimebotigiwatowalodowim.pdfIn PDF document text
    • http://www.thebetterinsurance.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b08baa1825c---18911370293.pdfIn PDF document text
    • https://sygimportaciones.com/wp-content/plugins/super-forms/uploads/php/files/968jupcuk2hfi1aio7v7kofed0/doliruxine.pdfIn PDF document text
    • http://verdantnorwich.com/clients/3/30/306756bb587dffcd11ca74610d845a16/File/jaxupaxupebadon.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/ngfLrbzwjls/uplcv?utm_term=nissan+240sx+automatic+to+manual+conversionPDF 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_off00013930.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13930 10956 bytes
SHA-256: d8272b6805fd7c4573303a31768402dcda76df679baed4e035a67f84d872c8de
font_01_sfnt_off000152b6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x152B6 18444 bytes
SHA-256: 0d71ab4020fe63d72168c5ddcbbfc900d7a48c7012c64921fbd1a0c991428864
font_02_sfnt_off000183f3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x183F3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1