Malicious PDF — malware analysis report

Static analysis result for SHA-256 c5ee75151b2c8552…

MALICIOUS

PDF

88.1 KB Created: 2021-10-12 12:44:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 20ccd8007176c1317598c5b4f8c1be2b SHA-1: c87575fe026377f5cae894eed4a5980d5aa88237 SHA-256: c5ee75151b2c85520d9aa13708d15ea69425297822cbd8bc4f2317a7d262c6c7
134 Risk Score

Malware Insights

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

The sample is a PDF containing embedded JavaScript, which is a common technique for delivering malicious content. The PDF also contains numerous external URIs, many of which point to disposable domains and are likely part of a link farm designed to obscure the true destination. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://greenhousehotel.vn/uploads/image/files/87913494486.pdf In PDF document text
    • http://aquitaine.annuaire-regional.com/ckfinder/userfiles/files/minuk.pdfIn PDF document text
    • http://tuvanluatdanang.com/upload/ck/files/pakofutexefosokupaf.pdfIn PDF document text
    • https://citrasas.com/ckfinder/userfiles/files/25949860719.pdfIn PDF document text
    • https://ladangmimpi.com/contents/files/25182256464.pdfIn PDF document text
    • https://hawkseyetravels.com/assets/ckfinder/userfiles/files/xukunefataredotanojov.pdfIn PDF document text
    • https://webbsoil.com/home/webb/public_html/ckfinder/userfiles/files/93358170421.pdfIn PDF document text
    • http://baobianhkhang.com/upload/files/77855761739.pdfIn PDF document text
    • http://ekmeta.lt/failai/file/82159089306.pdfIn PDF document text
    • https://www.fishhabitatnetwork.com.au/application/third_party/ckfinder/userfiles/files/22898682357.pdfIn PDF document text
    • http://www.laterveer-biesenbeek.nl/ckfinder/userfiles/files/10905408332.pdfIn PDF document text
    • http://yaqeen-eg.com/userfiles/file/84240837533.pdfIn PDF document text
    • https://31app.com/userfiles/file/33494616276.pdfIn PDF document text
    • https://vanphongphamhienluong.com/upload/files/36836848697.pdfIn PDF document text
    • https://www.alitec.es/js/ckfinder/userfiles/files/kivasaj.pdfIn PDF document text
    • https://drainscovers.com/wp-content/plugins/super-forms/uploads/php/files/6ed0e3372c33a60953ea22a98311df6f/1195501102.pdfIn PDF document text
    • http://mamaskitchenorder.com/uploads/files/9211607868.pdfIn PDF document text
    • http://svsteinfurth.de/radsportfiles/file/gixesezegopusigijoput.pdfIn PDF document text
    • http://shijijiaming.cn/filespath/files/20211009090449.pdfIn PDF document text
    • http://kenshopvn.com/uploads/files/zisexiliti.pdfIn PDF document text
    • https://ppntassone.it/dati/upload/file/745083683.pdfIn PDF document text
    • http://pm-property.pl/userfiles/file/kefajogovivozufitow.pdfIn PDF document text
    • http://feedproxy.google.com/~r/MbOu/~3/cmwvf4RlXg4/uplcv?utm_term=word+start+with+kPDF 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_off0000f1d1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF1D1 10232 bytes
SHA-256: 21d198523dd0d4b842c0d69b5747c2ef4f103df4510a92d0ab608f01d3c491f8
font_01_sfnt_off000108fa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x108FA 19768 bytes
SHA-256: a066d1b6294c741847b6e98da8f02195c7a423b25a9857d6c302dd733053b3a2
font_02_sfnt_off00013baa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13BAA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1