Malicious PDF — malware analysis report

Static analysis result for SHA-256 4131d24f5c5d1eb6…

MALICIOUS

PDF

81.9 KB Created: 2021-09-12 11:56:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: bac39f12e83b91cb57435ae0c6cceed5 SHA-1: 4e2aef6774a9a890f69f404e688fde0e8cd89fdd SHA-256: 4131d24f5c5d1eb63d7f290183a9395a4a44c0d2d21fb59ddb45802a55396ab5
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which are hosted on disposable domains and utilize UTM parameters, strongly suggesting a phishing or link-farming operation. The ML classifier and ClamAV detection further confirm its malicious nature. While no scripts were explicitly extracted, the PDF structure and embedded links are indicative of an attempt to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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 https://drafthe.ru/uplcv?utm_term=sqlite+asset+helper PDF link annotation
    • http://alacarte-grafik.de/userfiles/file/22085145236.pdfIn PDF document text
    • https://pasarant0g3l-turbo-h1t.com/contents/files/35523988104.pdfIn PDF document text
    • http://zulassungsservice4you.de/bilder/file/436366778.pdfIn PDF document text
    • http://nutranghongngoc.com/media/ftp/file/99946365886.pdfIn PDF document text
    • https://dom4m.com/userfiles/files/ralamipixakefujepifofiki.pdfIn PDF document text
    • https://clubsecurite.fr/webroot/upload/files/negavokopakabugiberakeji.pdfIn PDF document text
    • http://kanomax-nsk.ru/images/32047089945.pdfIn PDF document text
    • https://matricula.netlandschool.cl/files/12121288437.pdfIn PDF document text
    • https://zivotzaokny.eu/res/file/56762866229.pdfIn PDF document text
    • http://bdpq.hungminhits.com/files/uploaded/files/1749121661.pdfIn PDF document text
    • http://xn----ftbkdcamitb5h.xn--p1acf/files/fck/file/bitavegal.pdfIn PDF document text
    • https://tradingphrases.net/userfiles/files/tebinofeberawabegado.pdfIn PDF document text
    • https://floridainvestment.cz/files/file/zezasatewivajejapuvera.pdfIn PDF document text
    • http://xn--djr00fsyfv0o5qgy9u.com/filespath/files/20210911135505.pdfIn PDF document text
    • http://tubelessons.net/cms_images/file/litupaxupomoxiwozokira.pdfIn PDF document text
    • http://kramor.bg/userfiles/file/98553497660.pdfIn PDF document text
    • http://cuacuonnhaxuongbinhduong.com/upload/files/resokuxozekozifevufap.pdfIn PDF document text
    • http://halvani.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613cdac43b308---wololivoro.pdfIn PDF document text
    • http://fioredda.com/userfiles/files/92397619312.pdfIn PDF document text
    • http://hmed.vn/upload/files/12986059384.pdfIn PDF document text
    • http://ucg-eg.com/userfiles/file/76279664265.pdfIn PDF document text
    • http://www.ddu-hk.cz/ckfinder/userfiles/files/rawukumifojuxujasot.pdfIn PDF document text
    • https://www.indee-r.fr/wp-content/plugins/super-forms/uploads/php/files/856af90528ea93c65a3d8ef86649b14b/48497028547.pdfIn PDF document text
    • https://korovin.org/site/img_ufiles/dinopisiwuduxudunuk.pdfIn PDF document text
    • https://www.nstoplana.rs/ckfinder/userfiles/files/zewejorapakavekupuravulu.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_off0000d9e5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD9E5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f1f7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF1F7 19456 bytes
SHA-256: 196ea8a506c5c2aa262c0fc6ad04997dd9f1f71f6da2a3e8c492f337f8b28070
font_02_sfnt_off0001231a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1231A 10344 bytes
SHA-256: 7f7eec5fbfef400bb91c1f74852f7aef41681d038eceb9a732201c54bddb136e