Malicious PDF — malware analysis report

Static analysis result for SHA-256 ef98c595d8e2481c…

MALICIOUS

PDF

85.2 KB Created: 2021-09-13 11:53:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: df6610d4be733e53dfdbada4ed9c166e SHA-1: cdf749e2a4000f45834f28ee9255d658fbec4b9a SHA-256: ef98c595d8e2481cfa59de7735208bbfe4ec5439a18fddec391b2b04180d6527
134 Risk Score

Malware Insights

MITRE ATT&CK
T1059.007 JavaScript T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript, a common technique for executing malicious code within documents. The ML classifier and ClamAV detection strongly indicate malicious intent. The embedded JavaScript likely redirects to external URLs, as evidenced by the numerous PDF_URI and EMBEDDED_URL heuristics, suggesting a phishing or malware delivery scheme.

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 https://www.mds-horizons.com/upload/files/kuxobegabuwu.pdf In PDF document text
    • http://www.rosabrockenhaus.ch/ckfinder/userfiles/files/42499321308.pdfIn PDF document text
    • http://sky1981.com/asset/uploads/files/kuxutenetewitegivapegojaf.pdfIn PDF document text
    • http://gok-maciejowice.pl/js/ckfinder/userfiles/files/33105689180.pdfIn PDF document text
    • https://olterus.org/contents/files/tufipuweruvevavatojigud.pdfIn PDF document text
    • http://nguyenphat.com/public/default/ckeditor/files/12638050775.pdfIn PDF document text
    • http://www.videobezopasnost.ru/ckfinder/userfiles/files/mexekapexikekegoxega.pdfIn PDF document text
    • https://osikovo.eu/webroot/img/content/files/nopotoxu.pdfIn PDF document text
    • http://daedukgs.com/admin/fckeditor/data/file/20210902155430.pdfIn PDF document text
    • https://fortworthdental.net/cmsCart/upload/file/25697612416.pdfIn PDF document text
    • http://www.santabriganti.org/admin/ckfinder/userfiles/files/42020732226.pdfIn PDF document text
    • http://www.polni.si/Images/files/74082799112.pdfIn PDF document text
    • http://freemansphotography.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613d866257311---57648273705.pdfIn PDF document text
    • http://pphjako.pl/userfiles/file/jokonawanomesiwamafosifum.pdfIn PDF document text
    • https://webbsoil.com/home/webb/public_html/ckfinder/userfiles/files/93837596560.pdfIn PDF document text
    • http://deshpanday.com/ckfinder/userfiles/files/nizujekexop.pdfIn PDF document text
    • https://gea99.com/ckfinder/userfiles/files/tijatubivise.pdfIn PDF document text
    • https://edusfera.pl/upload/file/66173498666.pdfIn PDF document text
    • http://vallovin.it/userfiles/files/xenob.pdfIn PDF document text
    • https://okazionche.com/files/15906637595.pdfIn PDF document text
    • https://maconlux.lu/userfiles/files/tisejer.pdfIn PDF document text
    • http://www.ponderosafestival.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612fc155e5a3c---wibogasosevodapisokogim.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/zMnd8XtcwSM/uplcv?utm_term=how+to+take+a+screenshot+on+sc+without+them+knowingPDF 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_off0000e5f4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE5F4 10900 bytes
SHA-256: 852aee71f1afce01a23b6c3a310e7e9a9ecc7d86ce8522f6fd525b94ca31c28c
font_01_sfnt_off0000ff0b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFF0B 18300 bytes
SHA-256: 8c2314b679da27156a5c128a7119328d5dc8ffe7d0ad3cc04178e1f8c515db2c
font_02_sfnt_off00012e58.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12E58 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1