Malicious PDF — malware analysis report

Static analysis result for SHA-256 d840363853d56fbd…

MALICIOUS

PDF

76.6 KB Created: 2021-09-18 14:37:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: ff5c45b6ea0cdb7028a88085d07c0419 SHA-1: 27779fb041f8cf9e999158c3b3c842f282390bf6 SHA-256: d840363853d56fbddbf820523e8051702ec32593f6768a850ae02f8c06d057d4
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is identified as malicious by ML classification and ClamAV, with heuristics indicating it functions as a link farm. The PDF contains numerous embedded URLs, many pointing to potentially malicious domains, suggesting an attempt to redirect users to external sites. While no scripts were explicitly extracted, the PDF structure and the presence of many external links strongly suggest a phishing or malware distribution vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

Heuristics 5

  • 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.
  • 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://www.astmalek.cz/obrazky/file/tizalim.pdf In PDF document text
    • http://polipack.ru/content/file/posel.pdfIn PDF document text
    • https://pearproperties.in/userfiles/file/37137672950.pdfIn PDF document text
    • https://dortmundpools.com/contents/files/zunobamokenixibot.pdfIn PDF document text
    • http://metaglas.kr/userData/board/file/12003559229.pdfIn PDF document text
    • http://theleadershipworks.com/PO2/UPFILE/userfiles/files/17131274233.pdfIn PDF document text
    • https://biocenfis.es/uploads/assets/file/67028912923.pdfIn PDF document text
    • https://www.la-melodie-des-saveurs.fr/ckfinder/userfiles/files/32859926782.pdfIn PDF document text
    • https://biroestarsa.hu/uploads/file/31223834606.pdfIn PDF document text
    • https://gadapavimenti.com/GadaFiles/file/wonotoxe.pdfIn PDF document text
    • http://kashima.cc/userfiles/file/jagofegomasuwe.pdfIn PDF document text
    • http://yusungchart.com/userData/board/file/xosogefosenomakeregiko.pdfIn PDF document text
    • http://imagespa.mx/wp-content/plugins/formcraft/file-upload/server/content/files/16135e6bff3fa8---67154340807.pdfIn PDF document text
    • https://emergent-partners.com/wp-content/plugins/formcraft/file-upload/server/content/files/16137b7e7f1a45---seniworewuzekotu.pdfIn PDF document text
    • http://bunny888.com/ckfinder/userfiles/files/tezusux.pdfIn PDF document text
    • https://camelcarpet.org/d/files/23740236749.pdfIn PDF document text
    • http://dailyliving.nl/ckfinder/userfiles/files/30359649447.pdfIn PDF document text
    • http://hillsclinic.com/fckeditor/editor/filemanager/connectors/php/userfiles/file/lavekejasowedomi.pdfIn PDF document text
    • https://fotofidelity.cz/userfiles/file/49548370183.pdfIn PDF document text
    • http://salukool.ee/upload/userfiles/file/zomomevozubojujofidupira.pdfIn PDF document text
    • http://yaan121.com/uploads/files/202109040649077087.pdfIn PDF document text
    • https://psihodesk.ro/ckfinder/userfiles/files/rojomovatikowo.pdfIn PDF document text
    • http://tiga.co.th/ckfinder/userfiles/files/86868238740.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/FevRqgeaUVY/uplcv?utm_term=tom+gold+run+hack+apkPDF 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_off0000c9a4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC9A4 16820 bytes
SHA-256: 152b2821034c14b8f181277dbbc9fb7c584d407a4894c0a4be59466415a7e160
font_01_sfnt_off0000f50a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF50A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010d21.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10D21 10628 bytes
SHA-256: 3c941bcdf991068de381bf76f62652bc071683d46fe7105ccc954f86ca6adf2a