Malicious PDF — malware analysis report

Static analysis result for SHA-256 d4cb9dfefacf787c…

MALICIOUS

PDF

79.0 KB Created: 2021-09-17 23:43:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 0951428a72c056383d749c679391c665 SHA-1: 1a6840b7f67dde54418ab1f8a196043a6b8cb88e SHA-256: d4cb9dfefacf787c4954a6e9cae7550fa08fbe7fdb6e979e9fa2e94fb161f199
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and a high number of external URIs, many of which are part of a link farm. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to trick users into downloading further malware. The presence of embedded JavaScript suggests an attempt to exploit PDF vulnerabilities or redirect the user to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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 http://elskup.pl/images/assets/file/96618754710.pdf In PDF document text
    • http://stringquartet.biz/web/images/fck/file/18661549563.pdfIn PDF document text
    • http://sksound.com/userfiles/file/wodulejerisudaga.pdfIn PDF document text
    • http://swaptoys.org/ckeditor/uploads/files/89165431640.pdfIn PDF document text
    • https://sarna-zapiekanki.pl/ckfinder/userfiles/files/99257629188.pdfIn PDF document text
    • http://ilsogno-bomboniere.com/userfiles/files/47515026558.pdfIn PDF document text
    • https://mai-avto.ru/upload_files/file/90917006228.pdfIn PDF document text
    • https://elemental-ia.com/userfiles/file/pebijuzuxav.pdfIn PDF document text
    • http://karthikeyanjayaram.in/userfiles/file/zuxakiniwiwalanaxu.pdfIn PDF document text
    • http://webbuilders.com/files/file/zinilusipuxekerotazuk.pdfIn PDF document text
    • http://aliguoriarchitetto.eu/userfiles/files/zubumagotupapur.pdfIn PDF document text
    • http://deauville.ru/files/file/46196905198.pdfIn PDF document text
    • https://www.andimoda.com/wp-content/plugins/super-forms/uploads/php/files/dd2e4719fc8d10f6579fb37d84506932/42140183285.pdfIn PDF document text
    • https://mintowncoffee.net/uploads/images/files/labita.pdfIn PDF document text
    • https://keiba-like.biz/js/ckfinder/userfiles/files/runaxomija.pdfIn PDF document text
    • http://damosushipleasanthill.com/uploads/files/mozefi.pdfIn PDF document text
    • https://rajakeempat.com/contents/files/mulenedogemafuwexesu.pdfIn PDF document text
    • https://tradingphrases.net/userfiles/files/53419551550.pdfIn PDF document text
    • https://dtd.com.pk/ckfinder/userfiles/files/58157814199.pdfIn PDF document text
    • http://lirealestatelitigator.com/wp-content/plugins/super-forms/uploads/php/files/142f8a0f9f5288ad3c5a94ceb9b33730/32222462914.pdfIn PDF document text
    • https://bookmyexcellence.com/bookmyexcellence/js/ckfinder/userfiles/files/karuguso.pdfIn PDF document text
    • https://ckeditor.pamlskovnik.cz/ckfinder/userfiles/files/zipuwoxujemogufixawavafep.pdfIn PDF document text
    • http://abwrva.com/uploads/files/70715997188.pdfIn PDF document text
    • http://levne-pohary.cz/UserFiles/File/minigidupasunuxerukezi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=download+theme+manchester+united+for+androidPDF 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_off0000cfba.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCFBA 17700 bytes
SHA-256: baf37044b29bd2824d0b79d958231129a06796479df63b5ab423566f6733f7e9
font_01_sfnt_off0000fd02.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD02 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011519.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11519 10928 bytes
SHA-256: b1baa8ef30ab2f77c6796f520e8830c8c7400cfbaa414884206ff384f249c718