Malicious PDF — malware analysis report

Static analysis result for SHA-256 c589b83b28f88610…

MALICIOUS

PDF

82.0 KB Created: 2021-09-16 11:22:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 4dd9fe1628b9fcbf8d75063647da4b5f SHA-1: 8a8bdff7a7c168345df8d9903d2d7041df8401cb SHA-256: c589b83b28f8861090bf9d683a9aa0df7744da64045ae77468ee3246ee605ec4
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF file identified as malicious by ClamAV and an ML classifier. It contains embedded JavaScript, which is a common technique for executing malicious code within PDFs. The presence of numerous external URLs, many of which appear to be link farms or disposable hosting, suggests an attempt to redirect the user to malicious sites or download further payloads. The ML_NYX_PDF_MALICIOUS heuristic with a high score further supports the malicious classification.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9833

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 https://irlanc.ru/uplcv?utm_term=flappy+golf+codes+for+gold+eggs PDF link annotation
    • https://franchisebusinessadvisors.franchisebrokerwebsites.com/broker-site/files/files/doremanabi.pdfIn PDF document text
    • http://inwama4.vn/webroot/img/files/majinojagegamefadekej.pdfIn PDF document text
    • http://dennehylaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/kirarane.pdfIn PDF document text
    • http://sumtinathholidays.com/admin/uploadfiles/file/wefonewovenapegazogikuw.pdfIn PDF document text
    • https://kclandscapes.com/ckfinder/triplebuserfiles/file/53122433445.pdfIn PDF document text
    • http://xn--h1aeekk.xn--p1ai/files/file/zaxadupofonixegifiger.pdfIn PDF document text
    • http://zuche0551.com/upload/file/gifalimitides.pdfIn PDF document text
    • http://www.cpnatacao.pt/backoffice/ckfinder/userfiles/files/80932688473.pdfIn PDF document text
    • http://cgpreceptor.com/ckfinder/userfiles/files/xevafaropesuxaza.pdfIn PDF document text
    • http://lamexmarket.com/uploads/files/poxojafodibuwabi.pdfIn PDF document text
    • http://wujipacking.tw/upload/files/74731285602.pdfIn PDF document text
    • http://vouchertiket.com/airplane/ckeditor/uploads/files/lizin.pdfIn PDF document text
    • http://twozonechickenlasvegas.com/uploads/files/86547140889.pdfIn PDF document text
    • http://kesherisrael.com/uploadEditor/files/novipofek.pdfIn PDF document text
    • https://dampinggame.com/calisma2/files/uploads/letije.pdfIn PDF document text
    • https://natanashoes.com/kingkong/userfiles/files/vufodelof.pdfIn PDF document text
    • https://www.colegiodesafio.net/home/wp-content/plugins/formcraft/file-upload/server/content/files/16137eb5b08b41---jilejerigeralo.pdfIn PDF document text
    • http://zhfangyuan.com/uploadfiles/files/navotagunapa.pdfIn PDF document text
    • http://portamarioarchitetto.eu/userfiles/files/jegelunagemonajadoxil.pdfIn PDF document text
    • http://sarahscupcakery.com/wp-content/plugins/formcraft/file-upload/server/content/files/161316dacde116---darafape.pdfIn PDF document text
    • http://cathyourhair.nl/js/ckfinder/userfiles/files/larekikuvasibagexefonukur.pdfIn PDF document text
    • http://elosc.com/upFile/file///ITX202109130252119790.pdfIn PDF document text
    • https://postelezmasivu-liberec.cz/ckfinder/userfiles/files/66922517058.pdfIn PDF document text
    • http://studioriboldi.eu/userfiles/files/92575278708.pdfIn PDF document text
    • http://westernmaki.com/uploads/files/26692095345.pdfIn PDF document text
    • https://clickbox.ro/images/file/vesikevadiwodekutev.pdfIn PDF document text
    • http://xn--knstlerische-biografie-arbeit-lbd.ch/userfiles/files/70360229921.pdfIn PDF document text
    • 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_off0000dbab.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDBAB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f3bd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF3BD 17780 bytes
SHA-256: ec72ca7315dd798d879997204b1c51d76210701ad8c88dc7960a48f4d294849a
font_02_sfnt_off00012228.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12228 10592 bytes
SHA-256: 4aae419391102845de822f5c9a52f410d14d510d0c53810910fe1da5f3ae3d9a