Malicious PDF — malware analysis report

Static analysis result for SHA-256 ca36a62ea42e9079…

MALICIOUS

PDF

77.7 KB Created: 2021-09-21 04:10:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 83e79762fad0979fc37cd5c52d883eb4 SHA-1: b8655412492bff57b7d75934d7d798cdaffe7d1d SHA-256: ca36a62ea42e907934ba86039bbbf7c451741e5046a9275344a78eda97cff58a
104 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains an embedded JavaScript stream and numerous external URIs, many of which point to potentially compromised or disposable hosting. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a pattern of using numerous distinct hosts for a link farm, suggesting an attempt to obscure malicious destinations or leverage SEO tactics. The ML classifier strongly flags this PDF as malicious, supporting the conclusion that it is designed to redirect users to harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

Heuristics 6

  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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 https://energiadirect.pl/application/resources/ckfinder/userfiles/files/12065885656.pdf
    • http://www.wm-meyer.de/meyer/admin/editor/ckfinder/userfiles/files/9754783949.pdf
    • https://sport-jicin.cz/dokumenty/64695601633.pdf
    • http://dichvubaove.online/upload/files/2517307639.pdf
    • https://loyalangkorapartment.com/userfiles/file/luripuxaxo.pdf
    • https://lorenzonimmigrationlaw.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614919a771366---93378347357.pdf
    • http://botosani.ro/img/uploads/file/81312995716.pdf
    • http://www.pibmg.com.br/ckfinder/userfiles/files/files/nubonikikegerasokul.pdf
    • http://hnc2.com/userfiles/file/megarisisemubonirek.pdf
    • https://vsevolozhsk.mebel18.com/uploads/files/62215217760.pdf
    • https://xylemleads.com/userfiles/file/15998776519.pdf
    • https://brs.jo/userfiles/files/najazodozefufawugavijov.pdf
    • http://zovsh.com/Uploadfiles/files/lidojamaxek.pdf
    • http://brilliantsolarpaneling.com/userfiles/file/3212203001.pdf
    • http://0953057778.kad.tw/kads/ckfinder/userfiles/files/dawipubew.pdf
    • http://busto-wl.gattinonimondodivacanze.it/themes/userfiles/files/22855022476.pdf
    • http://hit-air.pro/ckfinder/userfiles/files/18111271333.pdf
    • https://sassanoproperties.com/FCKeditor/file/10645524645.pdf
    • http://acetuitioncentre.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16144410fe46c2---wisulisiliwelibumisor.pdf
    • http://southportrubbish.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613ded3a56e13---24573558773.pdf
    • http://stauarchitetti.eu/userfiles/files/20163497850.pdf
    • http://recepti.plovdivweek.com/js/ckfinder/userfiles/files/pebafelituxa.pdf
    • http://themultifold.com/wp-content/plugins/super-forms/uploads/php/files/gts9r2ggf9be7qvmd9aeeje6t1/tinupuwiberelu.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/BvfzZFkJO3s/uplcv?utm_term=sipgate+for+android
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000caa0.bin
4e20d390e18e0ed0c63c0e48b2c645de884be431ecacef4cdf93793180ecb434
pdf-font-stream PDF embedded font (sfnt) at offset 0xCAA0 17776 bytes
font_01_sfnt_off0000f8f6.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF8F6 16792 bytes
font_02_sfnt_off0001110d.bin
43ac29b92aa7ffbd379718026fc42ea7d1552ea5752f59861c0e25d8b9d6b10c
pdf-font-stream PDF embedded font (sfnt) at offset 0x1110D 10536 bytes