Malicious PDF — malware analysis report

Static analysis result for SHA-256 e4c54a418ace50f0…

MALICIOUS

PDF

84.8 KB Created: 2021-09-13 01:30:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 298bc75ae3602fe0d7077f60af63fddc SHA-1: fa359f84624c438fde956dbb9fa3aaebdb9f8f9c SHA-256: e4c54a418ace50f009bdb06afee5144287cbdabc9581d576a3247fdb14615f4c
164 Risk Score

Malware Insights

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

The sample is a PDF containing embedded JavaScript and multiple external URIs, many of which point to compromised CMS upload storage or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, specifically identified as phishing or a trojan. The embedded JavaScript and link farm structure suggest an attempt to redirect users to malicious sites for further compromise.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://xn--k1akb4c.xn--p1ai/userfiles/file/buwadopupelumi.pdf In PDF document text
    • http://www.eurosecurimed.com/ckfinder/userfiles/files/45236701295.pdfIn PDF document text
    • http://luckyassessoria.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16139168541848---29804569285.pdfIn PDF document text
    • http://newgoodluckcrane.com/admin/uploadfiles/file/30305128839.pdfIn PDF document text
    • https://hmv.ir/wp-content/plugins/formcraft/file-upload/server/content/files/161324978aed0c---dojavodamirutadiv.pdfIn PDF document text
    • https://ncfouting.com/wp-content/plugins/formcraft/file-upload/server/content/files/161319b00a9d95---funurilop.pdfIn PDF document text
    • https://nevisnews.com/userfiles/nemabumumezezawegiwi.pdfIn PDF document text
    • http://discarga.com/wp-content/plugins/formcraft/file-upload/server/content/files/16132cd532cadf---rujoneruwugapik.pdfIn PDF document text
    • http://bekkercoon.ru/ckfinder/userfiles/files/sigumuxut.pdfIn PDF document text
    • https://solener.info/ckfinder/userfiles/files/wipejusatexukitobebuwogar.pdfIn PDF document text
    • https://www.bussmann-tiefbau.de/ckfinder/userfiles/files/gadepogavikulepuxivizevi.pdfIn PDF document text
    • https://hoangphatdanang.xetnghiemadndanang.com/uploads/image/files/jopomobodupoko.pdfIn PDF document text
    • http://litho-and-co.fr/ckeditor/upload/files/32356256917.pdfIn PDF document text
    • http://mt-filtration.com/uploaded/file/1308964426131ce58ac7c0.pdfIn PDF document text
    • http://lionsmarsala.it/userfiles/files/73865112707.pdfIn PDF document text
    • http://tinavaron.com/ckfinder/userfiles/files/desejen.pdfIn PDF document text
    • http://anchor-m.com/js/upload/files/ruxunapidawe.pdfIn PDF document text
    • http://agroanaliz.by/upload/editor/files/zikubavajilawidoz.pdfIn PDF document text
    • http://unternehmensberatung-hegenbarth.com/userfiles/file/sivekovalites.pdfIn PDF document text
    • http://www.tramag.pl/upload/file/nevovivatepa.pdfIn PDF document text
    • https://letstravelforacause.com/miet/assets/files/36375578960.pdfIn PDF document text
    • https://terracetemayonetim.com/upload/ckfinder/files/86083765793.pdfIn PDF document text
    • http://wacommerce.net/home/integrity/public_html/ckfinder/userfiles/files/xozapoziloxanebobax.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/LPIa9PGmDLg/uplcv?utm_term=friday+night+funkin+minus+mod+apkPDF 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_off0000e66d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE66D 11048 bytes
SHA-256: c359734ed1f73205c513cd39fd7689ffb9c3581acfa2bf67869611541f9c4ce0
font_01_sfnt_off0000ffbe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFFBE 17480 bytes
SHA-256: 4a6ee9fedcb654d296186d9055eb5a6f1be4b4136231111bcbacba8ac0644051
font_02_sfnt_off00012d47.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12D47 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1