Malicious PDF — malware analysis report

Static analysis result for SHA-256 b3a0792001aea2be…

MALICIOUS

PDF

81.8 KB Created: 2021-09-21 21:13:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 55d217b98d941077fe5d88593a566d54 SHA-1: 5c54000dd65e184c49b1c7d0a1ee510509c12f13 SHA-256: b3a0792001aea2be9fe7c989b1f2ffd3c5e43b4a2f1cef7c0287fdf134dfadc3
104 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and a significant number of external URIs, many of which point to compromised CMS uploads or disposable hosting, indicating a link farm designed to redirect users. The ML classifier strongly flagged this PDF as malicious, supporting the conclusion that it is used for malicious redirection or phishing. The embedded JavaScript likely facilitates the redirection or exploits.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://ketchas.ru/uplcv?utm_term=sweet+home+3d+kitchen
    • http://kleinschadenexperte.com/userfiles/file/1094301877.pdf
    • http://www.hermosabeachbungalows.com/userfiles/files/32904671577.pdf
    • https://ixiu-23.com/uploads/files/202109171256419508.pdf
    • http://pretaporter-pegah.com/userfiles/file/20258519572.pdf
    • http://atlantichomeportugal.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614a141fc85af---25825418975.pdf
    • http://pro-group.ru/userfiles/file/xumutuforefogulezam.pdf
    • http://dspec-car.com/js/upload/files/jejak.pdf
    • http://polimak.pl/userfiles/file/zevopusi.pdf
    • https://www.hotelamoha.it/wp-content/plugins/formcraft/file-upload/server/content/files/1613d3f9e37833---91239081115.pdf
    • http://speednewslive24.com/assets/ckfinder/core/connector/php/uploads/files/denudiwosivinevaget.pdf
    • http://myhomeinparis.com/userfiles/files/tunevulawotijewojiz.pdf
    • https://szabolcsipeter.com/userfiles/file/46065211027.pdf
    • https://corcreation.twbiz.me/data/fckeditor/files/20210903_080134.pdf
    • http://bjerkelunden.org/content/files/userfiles/file///9690582928.pdf
    • https://www.intermediastudios.com.mx/wp-content/plugins/super-forms/uploads/php/files/9b574d09a3a330307e0587d3d8d81758/siwetitewawuketinobubegi.pdf
    • http://naszemotyle.natura2000.pl/imgturysta/files/64161234512.pdf
    • http://izumrud38.com/ckfinder/userfiles/files/janivusoniba.pdf
    • http://orzo.cz/uploaded/files/werif.pdf
    • http://daehwa.info/uploaded/file/42330184279.pdf
    • http://skyrunarser.com/js/fckeditor/editor/filemanager/connectors/php/connector.php/upfiles/file/210907052513019062yy4xla.pdf
    • http://www.como-grup.ro/fisiere/file/49959747491.pdf
    • https://guclupin.com/calisma2/files/uploads/rewugotudikakokufamas.pdf
    • http://www.qookspot.kitchen/wp-content/plugins/formcraft/file-upload/server/content/files/1614871b23efb8---58226855495.pdf
    • http://www.santabriganti.org/admin/ckfinder/userfiles/files/18959562130.pdf
    • 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_off0000dabd.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xDABD 16792 bytes
font_01_sfnt_off0000f2cf.bin
a7c147724bcdb7bfd50caa11f4c75760eb0a9c8e8e6a90e71fbefc842311917b
pdf-font-stream PDF embedded font (sfnt) at offset 0xF2CF 17992 bytes
font_02_sfnt_off00012168.bin
4188bff1eee50f710693e83b11e90144cab5fee2312493978ca0b30b3aa9602d
pdf-font-stream PDF embedded font (sfnt) at offset 0x12168 10584 bytes