Malicious PDF — malware analysis report

Static analysis result for SHA-256 b8e5d0c436bda8dc…

MALICIOUS

PDF

80.7 KB Created: 2021-09-09 14:04:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-29
MD5: a887ae52ec23abdc13599f0360ac4994 SHA-1: 0ebd2285eab272aff2f8495e59af50f7b0076dc7 SHA-256: b8e5d0c436bda8dc1aaa5073f9530697a33ff0d34c5289c1f722dcb5ba2bcf39
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external URIs, indicating it is designed to redirect users to potentially malicious websites. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic specifically points to a link farm strategy, likely for phishing or malware distribution. The ML classifier and ClamAV detection strongly support the malicious nature of this file.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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
  • 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://sziszolg.hu/editor_up/29710477942.pdf In PDF document text
    • http://phutungototuanphat.com/img-tvdl/files/43371715100.pdfIn PDF document text
    • http://alsace.annuaire-regional.com/ckfinder/userfiles/files/pugamubami.pdfIn PDF document text
    • https://olivermilk.vn/tctt/sites/aaa/file/xamulegewiveko.pdfIn PDF document text
    • http://ig-einheitsloks.de/medien/file/58775664439.pdfIn PDF document text
    • https://www.arc-welding.co.uk/wp-content/plugins/super-forms/uploads/php/files/hui3o1dri279hd44v8os2nv3ph/zusoxatepuribavekugudex.pdfIn PDF document text
    • http://tabbanbros.com/admin/fckeditor/editor/filemanager/connectors/upload/file/19126956131.pdfIn PDF document text
    • http://lotusromeo.fr/app/webroot/files/userfiles/files/vigezitoxexuwogowofabipu.pdfIn PDF document text
    • https://loyd.rs/images/file/kazutonuxaluvinefibejot.pdfIn PDF document text
    • https://hotelite.in/userfiles/file/wegamijonam.pdfIn PDF document text
    • https://www.twibiotech.com/plugin/ce1/ckfinder/userfiles/files/zatelaperipowemej.pdfIn PDF document text
    • https://cobrawire.com/userfiles/files/dukikoguvifasidaxerajeren.pdfIn PDF document text
    • https://efnnma.org/files/file/76149256567.pdfIn PDF document text
    • https://vasantviharproperties.com/userfiles/file/55646450960.pdfIn PDF document text
    • https://yumasri.com/assets/ckfinder/userfiles/files/kuwuguzijuju.pdfIn PDF document text
    • https://shidoremicrosys.com/media/98878522635.pdfIn PDF document text
    • https://yournew.site/wp-content/plugins/super-forms/uploads/php/files/bsbunjsl38faq4du2lrgvjgq3h/gekokutowi.pdfIn PDF document text
    • http://www.mueblesgamez.com/ckfinder/userfiles/files/7392825994.pdfIn PDF document text
    • http://sjccgy.com/userfiles/file/21476028686.pdfIn PDF document text
    • http://lycee-elm.org/userfiles/file/magelukidesug.pdfIn PDF document text
    • http://poltinka.ru/userfiles/file/dawuda.pdfIn PDF document text
    • http://xn----dtbhwhggdaoqfh3d.xn--p1ai/media/file/zozesuwetatikax.pdfIn PDF document text
    • http://dragonera.cn/admin/userfiles/file/nazexakovuvolabazuki.pdfIn PDF document text
    • https://shaplaconsulting.com/app/webroot/ckfinder/userfiles/files/xigowex.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/DOqCt-cVA4I/uplcv?utm_term=promo+code+reward+robuxPDF link annotation
    • https://www.assessment.unibe.ch/app/webroot/js/ckfinder/userfiles/files/piminaj.pdfIn PDF document text
    • 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_off0000d7ff.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD7FF 10452 bytes
SHA-256: 12217c9b8e98d484d8a3d54fcb409ca6cf63394ed5c610f220963274a19d5561
font_01_sfnt_off0000efd2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEFD2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000107e4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x107E4 17536 bytes
SHA-256: 1547293861b4961837662ef9ed5b3344f584062069fb190ff25279d15a94755a