Malicious PDF — malware analysis report

Static analysis result for SHA-256 61ae25a2d4a1d803…

MALICIOUS

PDF

70.6 KB Created: 2021-09-16 18:00:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 73c4d03e4be06d30a0fccf82c8126583 SHA-1: 868d623aa5be346613caeeddcf70f8a013608bd6 SHA-256: 61ae25a2d4a1d803e5bc6e4d94ba2e799bf205a3dd711a842c2b9015d4179349
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

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 numerous external URIs, many hosted on disposable domains, suggest a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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://infrive.ru/uplcv?utm_term=balancing+equations+worksheet+pdf PDF link annotation
    • https://tatsolarlight.com/uploads/files/81768641338.pdfIn PDF document text
    • https://designsdubaiukfashion.com/userfiles/file/19989243349.pdfIn PDF document text
    • http://ssteelelaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/73685938554.pdfIn PDF document text
    • http://www.oschouston.com/osc/wp-content/plugins/formcraft/file-upload/server/content/files/161402a577d24c---nufegugoxeg.pdfIn PDF document text
    • http://arcdesantmarti.com/biocop/Images/images-editor/file/gegebexakejekes.pdfIn PDF document text
    • http://asupuro.com/user_data/image/file/dugifezozirorovewa.pdfIn PDF document text
    • http://cokhihoaiduc.com/uploads/files/59438483422.pdfIn PDF document text
    • https://dentalrud.com/userfiles/file/44774861469.pdfIn PDF document text
    • http://biosafety.biz/ckfinder/userfiles/files/39427107119.pdfIn PDF document text
    • http://www.oschouston.com/osc/wp-content/plugins/formcraft/file-upload/server/content/files/16135ceee34378---banawavozifudazidigot.pdfIn PDF document text
    • http://sonhanint.com/uploadpic/sun/files/202109102104561553.pdfIn PDF document text
    • https://madspot.dk/ckfinder/userfiles/files/gojovakalewisuwaxabex.pdfIn PDF document text
    • http://terremeraude.com/userfiles/file/bejagu.pdfIn PDF document text
    • http://wingmanplanningdemo.com/userfiles/files/39899425758.pdfIn PDF document text
    • https://clickbox.ro/images/file/rafexaduto.pdfIn PDF document text
    • https://www.esfa.bg/root/ckfinder/userfiles/files/puredalejupixagutekog.pdfIn PDF document text
    • http://rayanchem.com/d/files/rutonefupuxarinanirik.pdfIn PDF document text
    • https://nuevocoach.co.uk/wp-content/plugins/super-forms/uploads/php/files/910ff72d8d46d99a7ffc9f0884d839c2/4849738705.pdfIn PDF document text
    • https://konferencii.ru/js/ckfinder/userfiles/files/72283947394.pdfIn PDF document text
    • https://styliststudios.com/imagesTE/file/divupivogaxugiju.pdfIn PDF document text
    • http://adgroup.co/userfiles/file/kisanavir.pdfIn PDF document text
    • http://mgmkt.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/161387d526a2d4---92196700427.pdfIn PDF document text
    • https://bititechnika.com/uploads/file/xepeg.pdfIn PDF document text
    • http://brandweeramsterdamamstellanden.nl/userfiles/file/jufimefuwulum.pdfIn PDF document text
    • https://ksdc.in/userfiles/file/81245860201.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_off0000b47b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB47B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000cc8d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCC8D 15028 bytes
SHA-256: 9b01c937c2d3b7a081a1cb6dc761f517c83fe1fb6c1ce886b9a30520802fe91c
font_02_sfnt_off0000f242.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF242 11376 bytes
SHA-256: 700a0fbcf5bcc9e63f66880d3d61358483e5f8427ef5790ace7af15ca06b9dad