Malicious PDF — malware analysis report

Static analysis result for SHA-256 a5fb20dc101e9d87…

MALICIOUS

PDF

84.7 KB Created: 2021-09-18 10:52:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: d7276c8752b92dc6f1f9301d6db57994 SHA-1: 22c470cb4cc5cd1327b2a3a6bc2dc7dbc4711b83 SHA-256: a5fb20dc101e9d87e0ae65cd3a5fa53636bb3bc51afd0f3f6a8d8843a219882d
164 Risk Score

Malware Insights

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

The sample is a PDF containing embedded JavaScript, which is a common technique for exploiting PDF viewers or delivering malicious content. The heuristics indicate a link farm pointing to compromised WordPress uploads and disposable hosting, suggesting an attempt to redirect users to malicious sites. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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 https://alkalacarservice.com/public_html/userfiles/file/bezelakulixatev.pdf In PDF document text
    • http://sdes.in/uploads/tonas.pdfIn PDF document text
    • http://battlegrouponline.com/app/webroot/js/ckfinder/userfiles/files/wajemilenu.pdfIn PDF document text
    • http://weiddy.com/uploads/files/202109131918378267.pdfIn PDF document text
    • http://encino.ilovepokebar.com/uploads/files/jijoruvafuwalin.pdfIn PDF document text
    • http://polishingmarblefloor.it/userfiles/files/9181898951.pdfIn PDF document text
    • http://tsrmvolontari.it/userfiles/files/ruvitofipipojuvukaduroto.pdfIn PDF document text
    • http://mebel-moscow.com/content/xuploadimages/file/medebisiduf.pdfIn PDF document text
    • http://sjmhospital.org/files/js/ckfinder/userfiles/files/60631686901.pdfIn PDF document text
    • https://vmkstroi.ru/wp-content/plugins/super-forms/uploads/php/files/c90a8f74ff56be8be62987a79c03adf8/94717518248.pdfIn PDF document text
    • https://pensiuneaselina.ro/userfiles/file/5459143644.pdfIn PDF document text
    • https://kildevangen.dk/files/rijizolopeji.pdfIn PDF document text
    • https://spheresignal.com/app/webroot/userfiles/files/3845352700.pdfIn PDF document text
    • http://traktorpulling.de/ablage/userfiles/files/vowakikimajakaxugubozuz.pdfIn PDF document text
    • https://www.energetisch-therapeut-estie.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1614171816ad48---zorako.pdfIn PDF document text
    • https://eternalbliss.net/file/puxoni.pdfIn PDF document text
    • https://lakecountyoralsurgery.com/wp-content/plugins/formcraft/file-upload/server/content/files/16144c991c3737---56269530541.pdfIn PDF document text
    • https://fasleh.net/Files/files/galudepebizetogemuset.pdfIn PDF document text
    • http://leadingedgecorporate.com/user_images/file/84058577170.pdfIn PDF document text
    • http://rootbeadmill.com/upload_fck/file/2021-9-7/20210907171923291519.pdfIn PDF document text
    • http://shortguycentral.com/ck_uploads/files/dikufetipesakixozebimopen.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/FevRqgeaUVY/uplcv?utm_term=download+pictures+from+samsung+phone+to+macPDF 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_off0000e416.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE416 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000fc28.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFC28 18004 bytes
SHA-256: 29be5305143b414a9bebdae21fee399d19139f59a5eb162cf9b137112542ff20
font_02_sfnt_off00012aed.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12AED 11252 bytes
SHA-256: 4638aa071dabf5c2ff4dda2461fd499172a4a4a3358461a295a3bef9c7f60665