Malicious PDF — malware analysis report

Static analysis result for SHA-256 b23920ee388b29cc…

MALICIOUS

PDF

75.2 KB Created: 2021-07-13 23:44:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: 1ae3967a866245fcd8bbb1f9177bf590 SHA-1: ba68b46c872f2a8ced4e2e47b2a737aa019212af SHA-256: b23920ee388b29cc8d522937669e69c9fe77ff98f39990166502039f9f2920b5
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs, many of which point to disposable hosting or compromised CMS uploads, indicating a link farm designed to redirect users. The primary purpose appears to be directing users to external, potentially malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9840

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
  • 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.
  • 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://vdadanang.vn/app/webroot/assets/files/fusamipo.pdf In PDF document text
    • http://schmetterlingsgaerten.de/file/givilutilokufegale.pdfIn PDF document text
    • http://alliance-ltd.com/userfiles/bavatarakudiriviwib.pdfIn PDF document text
    • http://agendaalzheimer.org/files/galeria/files/xutulexibu.pdfIn PDF document text
    • https://www.harasportcenter.com/wp-content/plugins/super-forms/uploads/php/files/fgv5ab07h72m4g2e5i9nqgaken/4431404868.pdfIn PDF document text
    • http://aliancegroup.su/wp-content/plugins/formcraft/file-upload/server/content/files/160a93b8520fb7---dapubepowedo.pdfIn PDF document text
    • https://chocoinmobiliario.com/wp-content/plugins/super-forms/uploads/php/files/7fc1415e759fb1ef52f13a1e158a7d15/sijikeluximupugalebur.pdfIn PDF document text
    • http://beulahcooleycollection.com/clients/870349/File/migimelino.pdfIn PDF document text
    • https://www.beadvised.co.uk/wp-content/plugins/super-forms/uploads/php/files/944f122ba7e720f4c91b45f67e87b591/kowugitenilenomipije.pdfIn PDF document text
    • http://sattamatkapatti.com/userfiles/file/60814016622.pdfIn PDF document text
    • https://www.aserspa.net/wp-content/plugins/super-forms/uploads/php/files/sn4i6mf7p2lh4s6gtjbuc1vn3u/rajagosovarupap.pdfIn PDF document text
    • https://www.jemelectric.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607a91be9af8f---rogareviga.pdfIn PDF document text
    • https://dtcprojects.com.au/wp-content/plugins/super-forms/uploads/php/files/o6c8lu2c4q4l0ksjojggfqbkkn/10305463022.pdfIn PDF document text
    • https://maidintown.co.uk/wp-content/plugins/super-forms/uploads/php/files/4cd42b91ef0284314c2e161ad48c84bf/66429204564.pdfIn PDF document text
    • http://shukokai-voves.fr/userfiles/file/mifunagubunimapora.pdfIn PDF document text
    • https://shriramsteels.in/public/ckfinder/userfiles/files/31212261764.pdfIn PDF document text
    • http://www.cuerpomenteyespiritu.es/wp-content/plugins/formcraft/file-upload/server/content/files/1609c4f8a60dc8---wimapofenefusoxepolazeg.pdfIn PDF document text
    • http://aksaaydinlatma.com/img/editor/image/file/1050375231.pdfIn PDF document text
    • http://acm-medicali.it/userfiles/files/sarevagafozalotisilafaf.pdfIn PDF document text
    • http://neilreardon.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/satadudanasekoz.pdfIn PDF document text
    • https://www.kiteschule-eckernfoerde.de/wp-content/plugins/formcraft/file-upload/server/content/files/16084226148cde---59580658451.pdfIn PDF document text
    • https://walkandsmile.com/userfiles/file/zasivoxenojenazenujajox.pdfIn PDF document text
    • http://pogologistics.com/ckfinder/userfiles/files/boxelaj.pdfIn PDF document text
    • http://famcareconnect.org/wp-content/plugins/formcraft/file-upload/server/content/files/160cb7b8d32a95---46219243811.pdfIn PDF document text
    • http://expertsystemgroup.com/file_media/file_image/file/jinavizuj.pdfIn PDF document text
    • https://nceptionsolutions.com/wp-content/plugins/super-forms/uploads/php/files/e2f1ec1f787c1afa67b92ebd3f904f1d/30243163725.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/GLLx1DTH0VQ/uplcv?utm_term=380+w+south+st+martinsburg+wvPDF 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_off0000c286.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC286 16368 bytes
SHA-256: 2eab81dcc2ee9a3c51cea62335ad889eacac7ab5ea02be3e34fa188022cd2232
font_01_sfnt_off0000ed36.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED36 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001054d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1054D 11172 bytes
SHA-256: 501c9955cf35d503a311537b97e04712363e9cd76be9efa7317fac3ec0386f24