Malicious PDF — malware analysis report

Static analysis result for SHA-256 373e6afd93d41cef…

MALICIOUS

PDF

69.4 KB Created: 2021-09-26 07:54:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 1a55c90387393269c555e36c2e4d929c SHA-1: b9efc9ef90cfe6ff18e8070b57e3d6d4752b76b1 SHA-256: 373e6afd93d41cef09480b0e6664a635e43683f965084f4e67ad062245f4fb36
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains an embedded JavaScript stream and multiple external URIs, with several heuristics indicating it functions as a link farm hosted on compromised or disposable infrastructure. The ML classifier and ClamAV detection strongly suggest malicious intent, likely to redirect users to phishing or malware sites. The embedded JavaScript is a common technique for initiating malicious actions within PDFs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9837

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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 http://mcutech.net/files/42975280625.pdf In PDF document text
    • http://www.rolstoellift.com/wp-content/plugins/formcraft/file-upload/server/content/files/16146578970a0e---vinuvufiga.pdfIn PDF document text
    • https://norservis.info/files/files/60141081479.pdfIn PDF document text
    • http://iccjsc.vn/images/uploads/files/xegapa.pdfIn PDF document text
    • http://monkey-do.net/userfiles/file/kekudiveluwedubam.pdfIn PDF document text
    • http://regalmotors-jp.com/js/upload/files/59972631663.pdfIn PDF document text
    • http://www.optionassurance.ca/wp-content/plugins/formcraft/file-upload/server/content/files/161334412b5c12---mogefelidiwiximusozeselug.pdfIn PDF document text
    • https://www.solucionaesp.com/ckfinder/userfiles/files/zosuliledoladisixono.pdfIn PDF document text
    • http://jenan.com/ckfinder/userfiles/files/dezedu.pdfIn PDF document text
    • http://files.ibiza-ferien.de/file/dasekavatipozejonel.pdfIn PDF document text
    • http://liubeauty.com/luutru/files/46734116886.pdfIn PDF document text
    • https://arranridingclub.com/fwd_docs/file/dosizirabogase.pdfIn PDF document text
    • http://zae.me/datafiles/file/66846314022.pdfIn PDF document text
    • https://hyosung-gulf.com/uploads/file/tovaxomusixufuvokek.pdfIn PDF document text
    • http://cnex.cc/images/blog/file/zugixagowoj.pdfIn PDF document text
    • http://www.teaterskolen-efteruddannelsen.dk/ckfinder/userfiles/files/linamowifetefiworug.pdfIn PDF document text
    • https://www.diktu.com/wp-content/plugins/formcraft/file-upload/server/content/files/16140eae38c132---bodaxodosun.pdfIn PDF document text
    • https://tradegateindia.com/userfiles/file/lovixuninugaguwajiroda.pdfIn PDF document text
    • http://scoutpate.com/userfiles/file/banizew.pdfIn PDF document text
    • https://fsreloading.com/userfiles/files/6020970586.pdfIn PDF document text
    • https://viveironativodevicosa.com.br/ckfinder/userfiles/files/voxamoba.pdfIn PDF document text
    • http://fli.edu.mn/ckfinder/userfiles/files/nusegapunoban.pdfIn PDF document text
    • http://longbienco.com/js/ckfinder/userfiles/files/livumonigibabakugeva.pdfIn PDF document text
    • http://www.bash.cl/media/file/duduwofuvuzumut.pdfIn PDF document text
    • https://legacydockandmarine.com/wp-content/plugins/super-forms/uploads/php/files/0fc2f1a970d4a644cf191c45b0bed813/miratijowelosubuj.pdfIn PDF document text
    • https://deycaterers.com/ckfinder/userfiles/files/xunipudonaka.pdfIn PDF document text
    • http://highlevel.pl/userfiles/file/fadadonavilapezoriwo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/fzgW7-mxBc0/uplcv?utm_term=gaming+wallpaper+phone+4kPDF 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_off0000b2c5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB2C5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000cadc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCADC 10728 bytes
SHA-256: df5cad9d3d9457e1b3ce39429f79a99c8a6ef1dfa323c5d114556e698f127883
font_02_sfnt_off0000e359.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE359 14796 bytes
SHA-256: a67115fd3892423e1002a0baeadbbca99c6c07a88df83609c64c33892397fedf