Malicious PDF — malware analysis report

Static analysis result for SHA-256 476ad42e342be5ae…

MALICIOUS

PDF

83.2 KB Created: 2021-09-05 00:29:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: b21d6f3274bd5668610414e8f904e2ce SHA-1: aace5655c9ff76ace32077263103a9fef9c31ef2 SHA-256: 476ad42e342be5ae51d8b4446363220017ff5dccb197c9a2c8e02c70da526187
156 Risk Score

Malware Insights

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

This PDF file was identified as malicious by ML classifiers and ClamAV, indicating it's likely a phishing or trojan delivery mechanism. The document functions as a link farm, with numerous embedded URLs pointing to compromised websites and disposable hosting, designed to redirect users to potentially harmful content. The presence of multiple compromised CMS upload links further supports its malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

Heuristics 6

  • 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.
  • 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://happyland-nsk.net/ckfinder/userfiles/files/56114192637.pdf In PDF document text
    • http://jointrilogy.com/wp-content/plugins/formcraft/file-upload/server/content/files/16082b427a5b8a---nulepagigotesebazivese.pdfIn PDF document text
    • https://masterok-kovka.ru/wp-content/plugins/super-forms/uploads/php/files/96f513b1c1a076691b9c7a0ed0f44c85/4466563986.pdfIn PDF document text
    • https://superchills.com/userfiles/file/16943959244.pdfIn PDF document text
    • http://www.predoisiasociatii.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1607e215d0b158---74747866193.pdfIn PDF document text
    • https://suemsas.com/wp-content/plugins/super-forms/uploads/php/files/3ut70pg4k1h82qefm4hd6s8dl7/85232962578.pdfIn PDF document text
    • http://naoshima-habitant.com/volenegijukel.pdfIn PDF document text
    • https://www.ideaklinikbakirkoy.com/wp-content/plugins/formcraft/file-upload/server/content/files/1610f2cbfa560c---73179311911.pdfIn PDF document text
    • https://e-fasteners.eu/media/file/niwojamurumojaremobiki.pdfIn PDF document text
    • http://cualuoiskydoor.com/webroot/img/files/33733280280.pdfIn PDF document text
    • http://xn--80aaae7amexjfdlfdfg.xn--p1ai/files/file/wegewesukapagowuxed.pdfIn PDF document text
    • https://barcelona-health.com/files/galeria/files/16296416891.pdfIn PDF document text
    • http://phucuongplus.com/upload/files/zugubopegivexosom.pdfIn PDF document text
    • http://www.studiolegalefusimorelli.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609a3c1445474---zaruwepijefoworiba.pdfIn PDF document text
    • http://densayhongngoai.com/uploads/userfiles/file/safapibuvijetowadi.pdfIn PDF document text
    • https://laughteronlineuniversity.com/images/upload/files/33579823789.pdfIn PDF document text
    • https://rolcsi-bau.hu/userfiles/files/patitixefiso.pdfIn PDF document text
    • http://citygclub.com/ckupload/files/ridawal.pdfIn PDF document text
    • http://cristalparkhotel.com/ckfinder/userfiles/files/33984524063.pdfIn PDF document text
    • http://davcpundri.com/css/file/44013117024.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3vuEKuznOb8/uplcv?utm_term=classroom+strategies+for+adhd+pdfPDF 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_off0000e350.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE350 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000fb67.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFB67 10872 bytes
SHA-256: c0414a712b1e5ea174e506c2dc1377f9eed73007bf58510ecec9afd801c4b6d1
font_02_sfnt_off00011451.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11451 16688 bytes
SHA-256: 00b21f47f5226b636b22adce9c11ba0713cb43298cd545af473730152273125b