Malicious PDF — malware analysis report

Static analysis result for SHA-256 8a4d35992958c6c8…

MALICIOUS

PDF

69.6 KB Created: 2021-09-27 17:10:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-21
MD5: 61ce0f1c7e32c7a936e7a7db8cb9e636 SHA-1: 2c07d25f4bab4f5ec8bb2fb24c44f49db0c9af1e SHA-256: 8a4d35992958c6c8b36ef0e5f07453b8fbaf66a9783a2bf0ae60373d508be53b
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external URIs, many of which point to disposable hosting. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic indicates a link farm designed to obscure the true destination, and the ML classifier and ClamAV detection strongly suggest malicious intent. The embedded JavaScript likely facilitates the redirection or download of further malicious content.

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 https://studiogreenwich.ru/wp-content/plugins/super-forms/uploads/php/files/e64c7684126d14063cf0b37cc3c1c400/4797179078.pdf In PDF document text
    • http://dgxzz.com/uploadfile/file/52755323908.pdfIn PDF document text
    • http://kxqcgs.net/filespath/files/20210924201744.pdfIn PDF document text
    • http://strahovka66.ru/userfiles/file/61505314214.pdfIn PDF document text
    • http://haustechnik-hagenauer.at/48058490430.pdfIn PDF document text
    • http://exms.fr/sites/default/files/file/sirinef.pdfIn PDF document text
    • https://firesystem.ro/imagini_ws/42061624668.pdfIn PDF document text
    • http://fobosgrunt.ru/files/ckfinder/files/33440859837.pdfIn PDF document text
    • https://sadhankendra.org/erc/media/luremofowope.pdfIn PDF document text
    • http://xn--krmer-dnnebacke-1kb72b.de/files/file/3011826655.pdfIn PDF document text
    • https://xn--72ca1bzcdf9cg5df4n5a8cei.com/userfiles/files/guwuwilefolazines.pdfIn PDF document text
    • https://detectagsafety.com/ckfinder/userfiles/files/93056973129.pdfIn PDF document text
    • http://musthighschool.mn/ckfinder/userfiles/files/71464943421.pdfIn PDF document text
    • http://jlsxjy.com/right/UploadFile/file///2021092111532073499.pdfIn PDF document text
    • https://alpinismbihor.ro/app/webroot/files/userfiles/files/kedupikupuwaro.pdfIn PDF document text
    • https://spcinternational.in/ckfinder/userfiles/files/72096778865.pdfIn PDF document text
    • http://russkiivopros.com/images/FCKeditor/file/famugozur.pdfIn PDF document text
    • https://people11people.gr/uploads/File/766530839.pdfIn PDF document text
    • http://kondicionery-fryazino.ru/upload_picture/file/20939228667.pdfIn PDF document text
    • http://aedjtj.pretty-match.com/upload/files/4642532297.pdfIn PDF document text
    • http://langmoon.jp/js/upload/files/turubigir.pdfIn PDF document text
    • http://sarljarry.fr/userfiles/file/41475172364.pdfIn PDF document text
    • https://oasis-travel.ro/files/wiwix.pdfIn PDF document text
    • http://dulichgiahy.com/upload/file/zogediwoso.pdfIn PDF document text
    • http://danies.ru/ckfinder/userfiles/files/wopuro.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3CAf4wW3hvY/uplcv?utm_term=psp+android+download+gamesPDF 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_off0000b2f4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB2F4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000cb06.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCB06 14844 bytes
SHA-256: b941ec27e5b9234c5de5759d2259cd5e25b1c0b55df184d4ee9741b60bb47af9
font_02_sfnt_off0000f062.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF062 10724 bytes
SHA-256: 161127f2894fe5d0a8c1ac52dd2ec4e0eea0965840dd9e30dd1e223a81fecc49