Malicious PDF — malware analysis report

Static analysis result for SHA-256 b616c5d6600339d3…

MALICIOUS

PDF

80.8 KB Created: 2021-09-11 04:44:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 0846a94819d90595af705e6109ee234f SHA-1: c4dbecc5ce5163bbed7773e5d1182911c091089d SHA-256: b616c5d6600339d376fa32d2902908943f72681e86309e7646184f39e4ccc292
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external URIs, with a high ML classifier score and ClamAV detection indicating malicious intent. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' suggests the document is part of a link farm, likely directing users to malicious sites. The embedded JavaScript is likely used to facilitate redirection or exploit vulnerabilities.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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
  • 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://piannocreativo.com/js/new/fckeditor/userfiles/file/fezilez.pdf In PDF document text
    • https://sunridgecorp.com/uploads/files/202109101843156861.pdfIn PDF document text
    • http://www.wiz-fac.com/uploadImg/file/53473530948.pdfIn PDF document text
    • http://fcgo.tw/uploadpic/files/60366580396.pdfIn PDF document text
    • https://ural-aiti.ru/admin/ckfinder/userfiles/files/zuwamurazut.pdfIn PDF document text
    • https://vcubusinesssolutions.com/userfiles/file/32569067672.pdfIn PDF document text
    • http://yanarfabrics.com/firma/files/25069780987.pdfIn PDF document text
    • https://electroagro.es/pub/files/68207256455.pdfIn PDF document text
    • http://akekaluck.com/ckfinder/userfiles/files/78163467969.pdfIn PDF document text
    • https://taumed.kz/upload/2021/09files/210908001353134187poxfr.pdfIn PDF document text
    • http://solmoda.it/userfiles/files/48772496228.pdfIn PDF document text
    • https://mimpishio.com/contents/files/xivogupifij.pdfIn PDF document text
    • http://lexprikson.com/admin/style/images/userfiles/file/48955053852.pdfIn PDF document text
    • https://viceda.com/userfiles/file/bogomisenaraberirukiwakal.pdfIn PDF document text
    • http://lawfirm.vn/MINH/user_files/file/xawuje.pdfIn PDF document text
    • https://next-engineering.com/userfiles/files/mavotematuvagikura.pdfIn PDF document text
    • https://www.golddustdental.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613bc8a0c2011---4734428355.pdfIn PDF document text
    • http://thegrcinstitute.org/app/webroot/js/ckfinder/userfiles/files/9954660882.pdfIn PDF document text
    • http://maxgear.cz/webpagebuilder/ckfinder/userfiles/files/xokonalebitowimunisa.pdfIn PDF document text
    • http://metaglas.kr/userData/board/file/gujosibunasezelakevoko.pdfIn PDF document text
    • http://aimic.com/userfiles/file/90070957899.pdfIn PDF document text
    • http://akademibt.com/resimler/files/majixapujilituneserixa.pdfIn PDF document text
    • http://amako-ra.com/wp-content/plugins/super-forms/uploads/php/files/95ab69819c76d8fd7d39d1c335be8eea/danejaxefavosi.pdfIn PDF document text
    • https://alkirbilaw.com/userfiles/files/vifakofavaxizuxi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3CAf4wW3hvY/uplcv?utm_term=seo+tools+keyword+checkerPDF 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_off0000d964.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD964 17216 bytes
SHA-256: 7d0a9ccc1ebaeb69504bc5c6dd51ac0298fc0f8d1fe1e1606d624c03caacdc2f
font_01_sfnt_off000105a4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x105A4 10476 bytes
SHA-256: 425f4875a9118e470c4241bb536b6aa69b134f82105228def2252410fc97867f
font_02_sfnt_off00011da9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11DA9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1