Malicious PDF — malware analysis report

Static analysis result for SHA-256 409c4c26662f8f08…

MALICIOUS

PDF

107.7 KB Created: 2021-10-08 06:20:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: a98fb5b9dcd0a46dfcd5a4b896fd00ac SHA-1: d9aed14763f440391d35ed6b9ed0754f79080e3b SHA-256: 409c4c26662f8f085fb5108b2663d0ca8bf96e901d259e0e44a3bd7712bce726
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 executing malicious code. The PDF also contains numerous external URIs, many of which point to unknown or potentially malicious domains, suggesting a phishing or malware distribution campaign. The ML classifier and ClamAV detection strongly indicate malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

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://rasciindia.com/firetech/ckupload/files/41646835209.pdf In PDF document text
    • http://daydeothe.vn/rich_editor/file/jawatokurakaxugiboxumuf.pdfIn PDF document text
    • http://letnipohar.cz/upload/file/futidotufijuzugunapo.pdfIn PDF document text
    • https://callmarkinvestments.com/callmark/files/97946791109.pdfIn PDF document text
    • http://abwmechanicsville.com/uploads/files/senuramasa.pdfIn PDF document text
    • http://www.martiusstaden.org.br/js/ckfinder/userfiles/files/godemovazadig.pdfIn PDF document text
    • https://psystat.net/candyticket/uploads/page_images/files/rafebitabaxuwiz.pdfIn PDF document text
    • http://mebel-moscow.com/content/xuploadimages/file/70621045289.pdfIn PDF document text
    • http://insuralead.com/userfiles/file/57802179901.pdfIn PDF document text
    • http://pamatudarbai.lt/ckfinder/userfiles/files/72990303663.pdfIn PDF document text
    • https://pelicanfinancialnetwork.net/ckfinder/userfiles/files/mawenigi.pdfIn PDF document text
    • https://fullmagicweekend.com/ckfinder/userfiles/files/41813079626.pdfIn PDF document text
    • http://anm-av.de/uploads/files/23239699619.pdfIn PDF document text
    • https://aquarell.ro/userfiles/file/89348457900.pdfIn PDF document text
    • https://suemsas.com/wp-content/plugins/super-forms/uploads/php/files/cmh37kl77eodmmc2eqq0m49fk0/rumisebusaj.pdfIn PDF document text
    • http://xprchemical.com/upload/files/15154971785.pdfIn PDF document text
    • http://szm.hu/userfiles/file/77904611128.pdfIn PDF document text
    • https://www.carnesvarejo.com.br/assets/ckfinder/core/connector/php/uploads/files/19049252331.pdfIn PDF document text
    • https://hiperaktivite.info/userfiles/files/20737374150.pdfIn PDF document text
    • http://alfavs.eu/userfiles/file/kupuz.pdfIn PDF document text
    • http://viethanit.vn/hinhanh/file/92147148312.pdfIn PDF document text
    • http://gennarimaq.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1615e0b6c96622---kikejuzafotapojizemuvidi.pdfIn PDF document text
    • https://perfecthospital.org/FCKeditor/file/zuzobifexag.pdfIn PDF document text
    • https://gitteszoneklinik.dk/ckfinder/userfiles/files/pobidokatepo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/S30rS-6n6vg/uplcv?utm_term=news+channel+viewershipPDF 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_off00013c06.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13C06 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00015418.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15418 20472 bytes
SHA-256: 298cb63fb5ab9a5e351415eaa6668d0f50fe5d9ff51824ca5b6e139b0f101f78
font_02_sfnt_off00018951.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x18951 10380 bytes
SHA-256: ecd76dca62ed85c19103d6e6ba869dcef1fda0badb16b330d259f7a7982247f3