Malicious PDF — malware analysis report

Static analysis result for SHA-256 3c343949a73992a0…

MALICIOUS

PDF

76.8 KB Created: 2021-09-17 22:37:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 4683da47296c215746ad71cb72884dd3 SHA-1: b65495413acdf8bbd6600e0ab85f5f571b55adfb SHA-256: 3c343949a73992a0ca7308d2c21b6eba7cf440a4711ac4e614d7669d60b12ee2
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. The PDF contains numerous embedded URLs, many of which point to potentially malicious PDF files, suggesting a link farm or redirection mechanism. While no scripts were explicitly extracted, the PDF structure and heuristic firings strongly suggest it's designed to exploit PDF vulnerabilities or trick users into visiting malicious sites, aligning with phishing or malware distribution tactics.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

Heuristics 5

  • 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.
  • 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://vucert.vn/uploads/files/rolobubilaraleweb.pdf In PDF document text
    • http://orthodoxvaidikasanghom.org/userfiles/file/43652008220.pdfIn PDF document text
    • https://liur-krd.ru/userfiles/file/fabesorofexusegejob.pdfIn PDF document text
    • https://agsposure.org/wp-content/plugins/super-forms/uploads/php/files/e99b99d19f2bbe19ed82907c326701a3/2241920255.pdfIn PDF document text
    • http://placidlakes.com/larpm/uploads/file/83415781849.pdfIn PDF document text
    • http://dongkoo.com/uploads/editor/files/niwixekapof.pdfIn PDF document text
    • http://sorokolaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/labobi.pdfIn PDF document text
    • https://mariellatriolo.it/public/file/muredafexasipeporanejodum.pdfIn PDF document text
    • http://xn--80ackbssfuieecff0e8c.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/kl01j40jk6ovrn9jqctkefcv16/karujikeve.pdfIn PDF document text
    • http://zhfangyuan.com/uploadfiles/files/79392978511.pdfIn PDF document text
    • http://cleversystems.ru/userfiles/file/rudatovo.pdfIn PDF document text
    • https://dadesigning.com/daduserfiles/files/navidenimajibovizikapo.pdfIn PDF document text
    • https://bbu.vn/Images_upload/files/pakedomepopepukasikug.pdfIn PDF document text
    • http://cozycornerexpress.com/uploads/files/sunegozuxedona.pdfIn PDF document text
    • http://ipai-bg.eu/img/file/52632955755.pdfIn PDF document text
    • https://ximatinhdongnai.com/app/webroot/files/images/pages/files/wisajenamexezaveba.pdfIn PDF document text
    • http://xn--nellieskche-0hb.de/userfiles/file/nototumerejunov.pdfIn PDF document text
    • http://mishor-uvk.com/uploads/files/dijodagubamuresosifekimaz.pdfIn PDF document text
    • http://studiotecnicomartani.eu/userfiles/files/xajusodofesava.pdfIn PDF document text
    • https://mcdelandes.ca/uploads/file/82962820143.pdfIn PDF document text
    • http://gesgo.de/userfiles/file/xufavebotaretenated.pdfIn PDF document text
    • http://fuyu.010bi.com/ckfinder/userfiles/files/61559473865.pdfIn PDF document text
    • http://bainihu.com/upfiles/editor/files/37846027970.pdfIn PDF document text
    • http://architettipassarinmarzotto.com/userfiles/files/55716807642.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/LPIa9PGmDLg/uplcv?utm_term=latest+android+sdk+tools+downloadPDF 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_off0000ca55.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCA55 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e267.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE267 16636 bytes
SHA-256: 63bf1f3c07594257d17dd934a02c17efe1a3a4dd0e1c9042f8149b68808b6d37
font_02_sfnt_off00010d63.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10D63 10376 bytes
SHA-256: e7dd3b0518147ad36839a51958a576ba49bb7d6e72e739ffbe582c2a95e9331d