Malicious PDF — malware analysis report

Static analysis result for SHA-256 485611e8a4b8ba5c…

MALICIOUS

PDF

74.9 KB Created: 2021-09-18 03:47:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: e9b51092e6e48e4dafad961fafab7df8 SHA-1: 6d44ba59e823d389cd479fbe2b85a0798f6ce1f7 SHA-256: 485611e8a4b8ba5cfd05750b3fc155450027b6b19ae06977bd7d2bf3894430ca
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was detected as malicious by ClamAV and an ML classifier, with heuristics indicating embedded JavaScript and a link farm pointing to potentially compromised WordPress uploads and disposable hosting. The embedded JavaScript likely facilitates the redirection or payload delivery, while the link farm aims to obscure the final destination. The presence of these elements suggests an attempt to lure users to malicious sites for phishing or further infection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9971

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://machnhaduong.com/images/uploads/files/99149066531.pdf In PDF document text
    • http://tdvvietnam.vn/webroot/img/files/mitaralatuxebakidesugupin.pdfIn PDF document text
    • http://daisin1977.com/js/upload/files/vomasanegafi.pdfIn PDF document text
    • http://zabradli-znerezu.cz/userfiles/file/46211163378.pdfIn PDF document text
    • http://asvpp.fr/pdf/mipitesoketowutov.pdfIn PDF document text
    • https://dichvumayphoto.vn/webroot/img/files/52858950622.pdfIn PDF document text
    • https://thehouseconcert.com/ckfinder/userfiles/files/54391251712.pdfIn PDF document text
    • http://urdu-hadith.com/survey/userfiles/files/43960382328.pdfIn PDF document text
    • http://drinkandshrink.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1613dd2edef235---xelozizelopaneforabavonos.pdfIn PDF document text
    • http://komodovo.ru/upload_picture/janoborikenokurugij.pdfIn PDF document text
    • https://realimpacto.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/161385c0d074cf---legugeramulapawikokijagov.pdfIn PDF document text
    • http://telegid.tv/userfiles/files/zufoxozasifujazokuvozunon.pdfIn PDF document text
    • http://bnblspecialities.com/userfiles/files/67484385295.pdfIn PDF document text
    • http://qdjshg.com/files/file/85991506699.pdfIn PDF document text
    • http://brunagabriele.it/userfiles/files/sovovefofugipapiba.pdfIn PDF document text
    • https://study-go.info/wp-content/plugins/super-forms/uploads/php/files/75866ba2369931163f49be3c13e452ef/11744471916.pdfIn PDF document text
    • http://kmsenior.org/file/files/gawajobigavewurutexep.pdfIn PDF document text
    • http://donaldnathanlaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/23039622163.pdfIn PDF document text
    • https://learn-atdi.com/uploads/files/88697700882.pdfIn PDF document text
    • https://homecareangels.ca/files/files/files/vanegepa.pdfIn PDF document text
    • http://shmgec.com/Uploadfiles/files/32402968553.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/DOqCt-cVA4I/uplcv?utm_term=a+quite+place+free+onlinePDF 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_off0000c409.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC409 16560 bytes
SHA-256: 9c48818d21b21c2dc0aeec0f0dd40204351e9cfafb7c8d9604d2fb7e7e1740a0
font_01_sfnt_off0000eea5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEEA5 10532 bytes
SHA-256: 2b51bb3af3bfd8a0acca11f9d3cb8b5ddcb48cf3863e8ac63569272e2a4845e2
font_02_sfnt_off000106bb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x106BB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1