Malicious PDF — malware analysis report

Static analysis result for SHA-256 681f33e1da1b49c1…

MALICIOUS

PDF

68.9 KB Created: 2021-10-02 19:25:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 00729573797e0906a511c97dde3f23a9 SHA-1: 66d6778cc7828c81f3a5ee6cdfebb67c6594b682 SHA-256: 681f33e1da1b49c19842c8df6c94e512a8c786f097692f953be124ff1f05d9bc
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. The PDF contains numerous embedded URLs, many of which point to disposable domains and are part of a link farm, suggesting a phishing or redirection scheme. While no scripts were explicitly extracted, the PDF structure and heuristic firings strongly suggest it's designed to exploit vulnerabilities or trick users into visiting malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9930

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://frankifoto.com/uploads/pages/files/35565322236.pdf In PDF document text
    • https://digitaldaya.com/imagenes/file/20113255696.pdfIn PDF document text
    • http://vit-physio.de/file/relokaloligita.pdfIn PDF document text
    • http://think6.net/ckfinder/userfiles/files/20210924060058.pdfIn PDF document text
    • http://fernandopelosini.it/userfiles/files/galubo.pdfIn PDF document text
    • https://habibitours.com/ckfinder/userfiles/files/sudeluraxedukanumifebufu.pdfIn PDF document text
    • https://easy2ticket.com/upload/files/70842078756.pdfIn PDF document text
    • https://mcq-exambd.com/app/webroot/ckfinder/userfiles/files/97854770319.pdfIn PDF document text
    • http://www.toptehnik.si/images/muxesisivarudufufop.pdfIn PDF document text
    • https://almuhja.net/ckfinder/userfiles/files/vuretividuduraz.pdfIn PDF document text
    • http://candientuvibra.com/images/file/32657075865.pdfIn PDF document text
    • https://ateneoarbonaida.com/wp-content/plugins/formcraft/file-upload/server/content/files/161572b281e67c---fuximusixejasulepevafereb.pdfIn PDF document text
    • http://yyfxsw.com/upload/files/21243464917.pdfIn PDF document text
    • http://www.dogwoodagility.nl/ckfinder/userfiles/files/waxezape.pdfIn PDF document text
    • http://teusz.pl/UserFiles/file/tizomudep.pdfIn PDF document text
    • https://shevtsov-art.com/uploads/files/nesitimurutupuvetumikikod.pdfIn PDF document text
    • https://bwawarszawa.pl/upload/file/22637540039.pdfIn PDF document text
    • http://baovecongtruong.com/upload/files/zerufuvipewatikufavesusur.pdfIn PDF document text
    • http://namadagaskare.ru/ckfinder/userfiles/files/5952981898.pdfIn PDF document text
    • https://mamadona.ru/ckfinder/userfiles/files/sepizepewibun.pdfIn PDF document text
    • https://hagabb.ro/ckfinder/userfiles/files/jupabelojaje.pdfIn PDF document text
    • https://www.adcgrain.com/wp-content/plugins/super-forms/uploads/php/files/51e8fc603ff104009df98b5023d0383e/66901982353.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1KS0DP0cxss/uplcv?utm_term=avengers+end+the+gamePDF 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_off0000aea5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAEA5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000c6b7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC6B7 15792 bytes
SHA-256: ce5f36b0db0b8542ace0b502b6e1545d3fee536aa4a684f8d1bbcfd5af626c82
font_02_sfnt_off0000ef0b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF0B 10484 bytes
SHA-256: 40e8992e4cb9cff52ce8543be5cfa6fa06f5a39d53dd68a235ee0072c59dd79e