Malicious PDF — malware analysis report

Static analysis result for SHA-256 ac2473c6831e8c78…

MALICIOUS

PDF

69.1 KB Created: 2021-10-03 13:38:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-21
MD5: b7058b41b40cde07a1cd7224bb7a47fc SHA-1: 5f62d85e2d2c6620265b38958c47d55c9e7da0a6 SHA-256: ac2473c6831e8c78a394b9b8df9d86847adf83c07d597fbf21f0b3bd0b7a0c0c
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF containing embedded JavaScript, which is a common technique for exploiting PDF vulnerabilities or redirecting users. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic indicates a large number of external links, many pointing to disposable domains, suggesting a link farm or phishing lure. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://ativn.com/upload/file/81810471012.pdf In PDF document text
    • http://luckdidea.com/ckfinder/images_store/files/gezodanuwimoxe.pdfIn PDF document text
    • http://zopos.zohukum.com/ckfinder/userfiles/files/60733226029.pdfIn PDF document text
    • http://acril.ru/ufiles/files/vugenokegenimowat.pdfIn PDF document text
    • http://mobilni-kadernictvi.cz/files/file/96366098473.pdfIn PDF document text
    • http://tv-sat.cz/userfiles/file/dasusemisepalomuvona.pdfIn PDF document text
    • http://tipkeo.com/js/ckfinder/userfiles/files/jefazujiwi.pdfIn PDF document text
    • http://sirinthepgroup.com/userfiles/file/64175651903.pdfIn PDF document text
    • https://www.indee-r.fr/wp-content/plugins/super-forms/uploads/php/files/3a28b8c2534f068d5ded8fbe4bcf7e6b/22410177529.pdfIn PDF document text
    • http://phanphoiongnhuahoasen.vn/upload/files/97832685360.pdfIn PDF document text
    • https://luxm.pl/userfiles/file/35326681802.pdfIn PDF document text
    • http://soloparamideco.com/js/new/fckeditor/userfiles/file/fopegedugubogumosuraberag.pdfIn PDF document text
    • http://miass.realxenon.ru/uploads/files/79369784297.pdfIn PDF document text
    • https://completecollegestrategies.com/wp-content/plugins/super-forms/uploads/php/files/b129af13634153845551d21bdb8e039f/99759602933.pdfIn PDF document text
    • http://wsm.hk/images/uploadfiles/file/rerefegoz.pdfIn PDF document text
    • http://palakkadtourism.in/ckfinder/userfiles/files/davobofogugidi.pdfIn PDF document text
    • http://dungcucaytrong.com/images/files/fufoli.pdfIn PDF document text
    • http://daugiavanthienphuoc.com/media/ftp/file/xizadizonebarapifodego.pdfIn PDF document text
    • http://girlstown.org/files/js/ckfinder/userfiles/files/wimaxepudabun.pdfIn PDF document text
    • https://bamfieldrental.com/userfiles/file/xotogop.pdfIn PDF document text
    • http://jd6618.com/jd6618/file/2021-9/file/LwpCms2021_09_23_12_24_28_6062.pdfIn PDF document text
    • http://sinproval.it/userfiles/files/murivobetewi.pdfIn PDF document text
    • http://www.fred-robin.com/ckfinder/userfiles/files/59292965597.pdfIn PDF document text
    • http://www.herbertvanderbrugghen.nl/draft/malikebemegukamu.pdfIn PDF document text
    • http://starma.pl/files/file/zorelevutopaxara.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/FevRqgeaUVY/uplcv?utm_term=as+far+as+i+can+meaningPDF 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_off0000b04d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB04D 10396 bytes
SHA-256: 094be136e9e9dd88426779d79b1dca27822ed5fbbd078d0b06b383a26d2f88b2
font_01_sfnt_off0000c7ca.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC7CA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000dfdc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDFDC 15420 bytes
SHA-256: 059f4cfe46949c7a5908ef614e77f754aff34374d01fbce39620f2f1293bada6