Malicious PDF — malware analysis report

Static analysis result for SHA-256 2ef4544e6d446ff2…

MALICIOUS

PDF

85.2 KB Created: 2021-09-12 18:54:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: b2b6031ff168ca9b6d7e3866b248eb68 SHA-1: 5536f06487417d19080e90b9d8a6ab114e886d86 SHA-256: 2ef4544e6d446ff2666225768e2aac2f7babe4441502b6a5c814c57c87f59d94
214 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1553.004 Security Software Installation

The PDF contains embedded JavaScript and multiple external URLs, with one heuristic specifically flagging it as a link farm. Crucially, it instructs the user to disable security software and mentions a password for an archive, strongly indicating a phishing or malware delivery attempt. The ML classifier and ClamAV detection further support its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9989

Heuristics 8

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Security software disable instruction high SE_SECURITY_BYPASS
    Document instructs the user to disable antivirus or security software — unusual for ordinary documents and high-risk in an unsolicited file
  • Password-protected archive handoff high SE_PASSWORD_ARCHIVE_LURE
    Document gives password instructions for an archive or attachment — often used to keep payloads encrypted until after gateway scanning
  • 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://gptools.net/userfiles/file/tesubakuz.pdf In PDF document text
    • https://natatourism.com/userfiles/files/8785985657.pdfIn PDF document text
    • https://hilanguage-com-tw.triangle-design.com/files/jefivabuxikufitupodumut.pdfIn PDF document text
    • https://dom4m.by/userfiles/files/ledusovuxojipakinuribo.pdfIn PDF document text
    • https://sunridgecorp.com/uploads/files/202109081447025950.pdfIn PDF document text
    • https://jamurgoreng.net/contents/files/jorumawawemixana.pdfIn PDF document text
    • https://securitydm.rs/slicice/file/57593075041.pdfIn PDF document text
    • http://sportsbettingconsultants.net/cote_dor_import/admin/ckfinder/userfiles/files/jiximopopeda.pdfIn PDF document text
    • https://mbamantra.com/ci/userfiles/files/88046481938.pdfIn PDF document text
    • http://www.espaciocultivarte.com/ckfinder/userfiles/files/38590980080.pdfIn PDF document text
    • http://xn--franzsischebulldoggen-lec.eu/userfiles/file/41416350463.pdfIn PDF document text
    • http://archetipoingegneria.it/userfiles/files/duberexovimurizixira.pdfIn PDF document text
    • http://studiotecnicoarduini.eu/userfiles/files/22530179387.pdfIn PDF document text
    • https://cliniquemyo.com/userfiles/file/11352089152.pdfIn PDF document text
    • http://www.martiusstaden.org.br/js/ckfinder/userfiles/files/rekanesu.pdfIn PDF document text
    • http://www.centrosanmarco.eu/img/news/files/tojodamimazo.pdfIn PDF document text
    • http://intranet.uts.edu.co/portal/app/ckfinder/userfiles/files/53901033444.pdfIn PDF document text
    • http://coachhouse.info/assets/file/63160727856.pdfIn PDF document text
    • https://www.edutechusa.com/wp-content/plugins/formcraft/file-upload/server/content/files/16139ddf564526---61448074040.pdfIn PDF document text
    • http://patroha.hu/file/gavagobanuxupilufemone.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/A3Ryygt5BCM/uplcv?utm_term=kmspico+windows+10+activator+free+download+full+versionPDF 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_off0000e524.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE524 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000fd3b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD3B 11200 bytes
SHA-256: 388c20bfafe9055d0d233bcbe04ddc7fa95439459b08c23f33ccbbbe2baae008
font_02_sfnt_off00011789.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11789 18016 bytes
SHA-256: 6beaea05e70b8814bbf1b43714844588431c529ebfbe068b01d8d4b3038291fa