Malicious PDF — malware analysis report

Static analysis result for SHA-256 b56ab16e10f06f20…

MALICIOUS

PDF

69.0 KB Created: 2021-09-26 23:10:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 4a9858185886e6c5a6c9bc2d671f78e0 SHA-1: 838c70ee1e54ff65a114d73d9a336a6d8783dc6a SHA-256: b56ab16e10f06f2025664cdf8087d4deb8dd277b0b83b4585ee593f8cda90f87
134 Risk Score

Malware Insights

The sample is a PDF containing embedded JavaScript, which is a common technique for malicious PDFs. The PDF also contains a large number of external URIs, many of which point to disposable domains, suggesting a link farm or SEO manipulation tactic. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9959

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://krygina40.ru/UserFiles/File/xomidajukoxum.pdf In PDF document text
    • http://www.idukkidiocese.org/files/js/ckfinder/userfiles/files/99669332456.pdfIn PDF document text
    • https://baxsporthorses.com/userfiles/file/roxipatebivuxiruburebug.pdfIn PDF document text
    • http://engcaphone.com/_UploadFile/Images/file/59412802540.pdfIn PDF document text
    • https://www.projectorrentals.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614faa26e5b1c---70906523909.pdfIn PDF document text
    • http://omgmediatank.com/userfiles/files/bavodewaje.pdfIn PDF document text
    • http://citygclub.com/ckupload/files/77386976321.pdfIn PDF document text
    • https://terminal.hr/userfiles/file/74224560621.pdfIn PDF document text
    • https://groupekheidri.com/ckfinder/userfiles/files/xevutemezediziwidemokewa.pdfIn PDF document text
    • https://agriplan-rs.com/dados/ckfinder/files/55746940281.pdfIn PDF document text
    • https://rumusjitu.com/contents/files/parelefudoleturiwiwib.pdfIn PDF document text
    • http://networkinglikepro.com/ckfinder/userfiles/files/8734426286.pdfIn PDF document text
    • https://thehouseproduction.net/file/bamurokafesodu.pdfIn PDF document text
    • https://hoangvan.vn/wp-content/uploads/files/buninexexut.pdfIn PDF document text
    • http://balie.overeembv-profielen.nl/upload/files/sinazonogon.pdfIn PDF document text
    • http://designerhouse.ru/upload/files/90265609257.pdfIn PDF document text
    • http://careerhack.net/wp-content/plugins/formcraft/file-upload/server/content/files/161393b72f2795---35421084567.pdfIn PDF document text
    • http://www.casasemio.com.br/ckfinder/userfiles/files/katokefemuxaja.pdfIn PDF document text
    • http://stlukesfp.org/ckfinder/userfiles/files/kekoj.pdfIn PDF document text
    • http://kursadowicz.pl/Upload/file/tinakobuzesuxelaramib.pdfIn PDF document text
    • http://terezszilvia.com/images/uploaded/file/bomabuzeliromusobe.pdfIn PDF document text
    • http://aksaaydinlatma.com/img/editor/image/file/bimoduxeta.pdfIn PDF document text
    • http://radio-salsa.fr/php/rs/filesupload/file/tejexopapikuwoj.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/cv9VXjIrmdE/uplcv?utm_term=samsung+galaxy+mobile+checking+codePDF 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_off0000ade5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xADE5 11244 bytes
SHA-256: e28f59ade5a72671968aa85d2cadcc50ef57c0c8f8da7d93d6b4f825ee28e64f
font_01_sfnt_off0000c7da.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC7DA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000dfec.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDFEC 14732 bytes
SHA-256: 89558054e87eee2d9ffb3eba221b5e0720ae78a0ce32be8775ffbaadaa57e1af