Malicious PDF — malware analysis report

Static analysis result for SHA-256 15dc9ce2eaf3401b…

MALICIOUS

PDF

81.1 KB Created: 2021-09-13 23:50:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 8a50d3221eb972204cfb729bc1e2ced8 SHA-1: eb704dfebdbf86f7fd33211bce5c100d998bc470 SHA-256: 15dc9ce2eaf3401bf8bf8a6f0b348b9cf6ca04ca24682ef52163de118b5b6adf
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as a malicious PDF by ClamAV and an ML classifier. It contains numerous embedded URLs, many of which point to suspicious PDF files on various domains, suggesting a link farm or redirection mechanism. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic indicates a pattern of using disposable hosting for these links, commonly seen in phishing or malware distribution campaigns. While no scripts were explicitly extracted, the nature of the embedded links and the overall detection strongly suggest an intent to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://leylasuren.com/images/userfiles/imagefile/sujilubup.pdf In PDF document text
    • http://1mosref.ru/ckfinder/userfiles/files/dopixoxupasodudexa.pdfIn PDF document text
    • https://ubk-sad.de/azubi/userfiles/files/25053977125.pdfIn PDF document text
    • http://laboratoriodiprogettazione-ve.it/userfiles/files/35830297078.pdfIn PDF document text
    • http://poongdung.com/FileData/ckfinder/files/20210906_73E1C65E0B4011FA.pdfIn PDF document text
    • https://valleyrentals.com/userfiles/file/19121922626.pdfIn PDF document text
    • http://philipp-haberland.de/images/upload/file/rolupokeramaxifilepapomu.pdfIn PDF document text
    • https://cebrigantina.com/025-CEB/images-editor/file/73590512263.pdfIn PDF document text
    • https://totalyoumovement.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613963246fb22---ditef.pdfIn PDF document text
    • http://liccuza.ro/stiri_files/file/giwogikojunajofu.pdfIn PDF document text
    • http://robwalker.net/fckupload/file/tifali.pdfIn PDF document text
    • https://www.soroptimist.be/oldsite/intranet/ckeditor/ckfinder/userfiles/images/files/tejunobaxoled.pdfIn PDF document text
    • https://kurishupally.org/userfiles/file/fegew.pdfIn PDF document text
    • http://autoscuolepintozzi.it/userfiles/files/94410197894.pdfIn PDF document text
    • http://tdvvietnam.vn/webroot/img/files/ketisa.pdfIn PDF document text
    • https://pindimana.in/uploads/file/vonemepo.pdfIn PDF document text
    • http://kocavietnam.com/upload/files/govaworego.pdfIn PDF document text
    • http://becucci.it/userfiles/files/63567101139.pdfIn PDF document text
    • http://tythb.com/uploadfile/files/28152513525.pdfIn PDF document text
    • https://imagebuzz.net/ckfinder/userfiles/files/17217874339.pdfIn PDF document text
    • http://uyaviation.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613154a1675b3---46139612721.pdfIn PDF document text
    • https://ratosatu.com/contents/files/lavorajemumagajuto.pdfIn PDF document text
    • http://oryginalnedekoracje.pl/userfiles/file/kadoxoril.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/PmAiG5ZyT-k/uplcv?utm_term=photo+editor+pixerist+fx+pro+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_off0000d57d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD57D 10640 bytes
SHA-256: e658b13db50e36c5eb4cec158d2504bf1395de1a90cdffb28988ea0f5eaa8ea3
font_01_sfnt_off0000ee07.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE07 18500 bytes
SHA-256: 0bdd1901418e91e937cbbce0e414d959a652966e11e793c03e480188e71144e9
font_02_sfnt_off00011e7e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11E7E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1