Malicious PDF — malware analysis report

Static analysis result for SHA-256 b4df0ef253e0c980…

MALICIOUS

PDF

82.9 KB Created: 2021-09-16 17:20:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 724e6e4b2d4bc4cc940ce00c2eb9a275 SHA-1: d9d3d441cc610679aa1b8be91dc317e4914d20a5 SHA-256: b4df0ef253e0c980f6d5e067b696da899949b7a71435f4d82770abb0ec23af60
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript, a common technique for executing malicious code within documents. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' and the numerous extracted URLs suggest a phishing or spam campaign aiming to redirect users to potentially malicious sites. The ML classifier and ClamAV detection strongly indicate malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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 https://dreptultau.hotnews.md/upload/userfiles/files/joragavozige.pdf In PDF document text
    • http://studiolegalezullo.eu/userfiles/files/fikiviporuroro.pdfIn PDF document text
    • http://www.martiusstaden.org.br/js/ckfinder/userfiles/files/nupupepiruje.pdfIn PDF document text
    • http://avstralianature.ru/ckfinder/userfiles/files/47087252456.pdfIn PDF document text
    • http://jubileejec.com/userfiles/files/tumenopezotepinoxugez.pdfIn PDF document text
    • http://capitolmetrophysicaltherapy.com/userfiles/file/sajesu.pdfIn PDF document text
    • http://erulingua.hu/uploads/content_files/files/pevobeve.pdfIn PDF document text
    • http://tl-maskinfabrik.dk/userfiles/file/mijebujakus.pdfIn PDF document text
    • http://brenna-ski.pl/userfiles/file/ridixag.pdfIn PDF document text
    • https://www.taxikladis.gr/wp-content/plugins/formcraft/file-upload/server/content/files/1612f46db07fd6---92546405870.pdfIn PDF document text
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/16136069ab1c4d---45598680656.pdfIn PDF document text
    • https://fokusmedia.com/images/uploads/74855702282.pdfIn PDF document text
    • https://machnhaduong.com/images/uploads/files/64081731814.pdfIn PDF document text
    • http://uteambio.com/upload/files/51728515979.pdfIn PDF document text
    • http://gongin.humenia.com/upload/userfiles/2021/09/files/210909072359.pdfIn PDF document text
    • https://businesslife.com/content/file/58886782380.pdfIn PDF document text
    • https://airbays.com/userfiles/file/6008545952.pdfIn PDF document text
    • http://testsitehq.com/ckeditor-ckfinder-integration/uploads/files/83823411183.pdfIn PDF document text
    • https://longislandinvestmentadvisors.com/nini/userfiles/file/webarulomepigunafikam.pdfIn PDF document text
    • http://abworder.com/uploads/files/63136299277.pdfIn PDF document text
    • http://creativetechno.in/userfiles/file/nekazunovobobe.pdfIn PDF document text
    • http://lica.plovdivweek.com/js/ckfinder/userfiles/files/sogowaxojadipuxajexili.pdfIn PDF document text
    • https://campermagazine.tv/public/file/28959902910.pdfIn PDF document text
    • https://hsse.hssanesteban.cl/files/xiwujifetir.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/fzgW7-mxBc0/uplcv?utm_term=minecraft+survival+base+inspirationPDF 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_off0000e1ed.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE1ED 16740 bytes
SHA-256: a79310177212ca3f55c07109ec738236a021baeda0e3f9bcaaf017ed8ea4af2a
font_01_sfnt_off00010cde.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10CDE 10772 bytes
SHA-256: 4e16d085eaec607373593838a68521d9820cbae48ac59dccaf2130dcd12dde19
font_02_sfnt_off0001259b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1259B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1