Malicious PDF — malware analysis report

Static analysis result for SHA-256 b8853ed26633077a…

MALICIOUS

PDF

78.1 KB Created: 2021-09-19 20:47:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 263ead2e74a2ff8ad59167ca7cf9e2a1 SHA-1: 77d6267dc1fbc1e165e212be9e7aaad33a79237b SHA-256: b8853ed26633077af9e8b3acad95362cd8a37c19a6508c73f071213f96b8d3aa
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The sample was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains embedded JavaScript, which is often used to exploit PDF vulnerabilities or redirect users to malicious sites. The PDF also acts as a link farm, pointing to numerous external PDF files, suggesting a distribution or phishing campaign.

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 https://vialivonica.eu/userfiles/files/87529576441.pdf In PDF document text
    • http://adasbruiloften.nl/userfiles/file/23012994169.pdfIn PDF document text
    • https://tcremich.lu/files/files/67594135728.pdfIn PDF document text
    • http://net-work.cz/data/file/lijaxejofi.pdfIn PDF document text
    • http://atrsara.ir/resource/files/pazuruvoraj.pdfIn PDF document text
    • http://kazenergy.kz/wp-content/plugins/formcraft/file-upload/server/content/files/161385e0566c72---90230575682.pdfIn PDF document text
    • http://ondrejkocar.cz/img/file/42949162749.pdfIn PDF document text
    • http://stagegator.scorchmark.com/stagegator/ckfinder/userfiles/files/wevaziwivazotevinikoxoxo.pdfIn PDF document text
    • https://hsse.hssanesteban.cl/files/lalaroramivepupa.pdfIn PDF document text
    • http://yavuzselimvakfi.org/resimler/site/files/bajukudakodipefinirit.pdfIn PDF document text
    • http://cana.vn/uploads/userfiles/file/99676163687.pdfIn PDF document text
    • https://novinfasteners.com/userfiles/file/31953228954.pdfIn PDF document text
    • http://palyavalaszto.hu/teszt/upload/file/30996079397.pdfIn PDF document text
    • http://nguyenphat.com/public/default/ckeditor/files/tibalawitevodog.pdfIn PDF document text
    • http://capri.lt/userfiles/files/tosexifefepufot.pdfIn PDF document text
    • http://www.martiusstaden.org.br/js/ckfinder/userfiles/files/88010008150.pdfIn PDF document text
    • https://tallerescarrion.com/uploads/file/tajikivunokiwurujul.pdfIn PDF document text
    • http://khyljg.com/uploadfiles/files/kaduwugarulut.pdfIn PDF document text
    • https://burlingame.com/wysiwygfiles/file/59007697658.pdfIn PDF document text
    • https://mbbs.hr/files/gataj.pdfIn PDF document text
    • https://advik.net/userfiles/file/8658606278.pdfIn PDF document text
    • http://highdesertrent.com/newsite/images/uploads/file/8906292144.pdfIn PDF document text
    • https://yarpaket.ru/userfiles/file/30726374733.pdfIn PDF document text
    • https://bedandbreakfastchia.it/userfiles/file/26685631130.pdfIn PDF document text
    • http://serviphony.com/tinymce/jscripts/tiny_mce/plugins/phpimage/phpimage/upload/images/file/79138773056.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/A3Ryygt5BCM/uplcv?utm_term=quick+shortcut+maker+apk+6.0+downloadPDF 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_off0000cabc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCABC 16992 bytes
SHA-256: 9550a923b28b790f8d02d52728d2befcaf27a685553ea3acdacb42df93f060d5
font_01_sfnt_off0000f6ca.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF6CA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010ee1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10EE1 11472 bytes
SHA-256: 577c854eeeab4289c78e85133c2d3e93ad7a1ea79d24dbf6a6a232bb7613379a