Malicious PDF — malware analysis report

Static analysis result for SHA-256 50ed9a7e4e51a87d…

MALICIOUS

PDF

76.3 KB Created: 2021-09-26 17:47:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 96a871ef431f131d56c91022984b7d26 SHA-1: 5183486a8660c781e1ce189fc4ad127f3b549b81 SHA-256: 50ed9a7e4e51a87d200d8fddfde50ca0c55330902a73ee38a8c1124dc5bd5334
164 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 upload directories. The ML classifier and ClamAV detection strongly indicate malicious intent. The embedded JavaScript likely facilitates the redirection to these malicious links, which are designed as a link farm to obscure the true destination and potentially deliver further malware or phishing content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9963

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://catamma.ru/uplcv?utm_term=yk+lim+quantum+mechanics+pdf
    • https://marciasmithconsulting.com/wp-content/plugins/super-forms/uploads/php/files/5196040bd77bb3d40ea5a45451bd986e/zeduzevad.pdf
    • http://tydafa.com/dafa/uploadfiles/20210926115003.pdf
    • http://dc-42351dc5a6b3.prshots.es/uploads/userfiles/1630966139/files/11008910355.pdf
    • https://ateneoarbonaida.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614e5e337b5f7---ginovosoresowexubom.pdf
    • http://www.rlktechniek.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1613e3388b6e12---11789704871.pdf
    • https://123kozijnofferte.nl/wp-content/plugins/super-forms/uploads/php/files/fb42b93c8a959d39fce07090fae51a1d/20873757566.pdf
    • http://rasciindia.com/firetech/ckupload/files/9956202957.pdf
    • https://cardion.dk/gfx/fckimages/file/wobogapesopopunam.pdf
    • http://xn--80aer5aza.xn--19-kmcm3c.xn--p1ai/ckfinder/userfiles/files/72260853694.pdf
    • http://lawyersmarketingusa.com/user_upload_image/file/
    • http://sun-green.be/ckfinder/userfiles/files/19168480051.pdf
    • http://huynhgiabaohotel.com/uploads/FCK/file/96500672998.pdf
    • http://kawana.tech/userfiles/file/97604546157.pdf
    • http://perechen-izdaniy.ru/js/ckfinder/userfiles/files/xibatavoxon.pdf
    • https://serpavenger.com/ckfinder/userfiles/files/78745113666.pdf
    • https://bostaninsaat.com/image/files/zudasapokamigu.pdf
    • http://rvhifi.cz/files/file/kibanajogera.pdf
    • http://autoservizimensi.it/images/fck/file/nedagat.pdf
    • http://prodottoitalia.eu/userfiles/files/sepovanizopuwifetevomilom.pdf
    • http://www.trimbleexpress.sk/wp-content/plugins/formcraft/file-upload/server/content/files/16141fd0f965f9---nibaxatomuvujigekol.pdf
    • https://gresathouse.com/wp-content/plugins/super-forms/uploads/php/files/581ea1f6cb0353ba087c96f9aa4bbbef/dibasamavinizaxowelo.pdf
    • http://sanalights.com/admin/admin/uploadfiles/file/kijigepupoli.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_off0000bdb9.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xBDB9 16792 bytes
font_01_sfnt_off0000d5d0.bin
2cd42322318cb7e669b6d39da3dd3130e2725b81bbd5a53c9ca765eb04e7cf5c
pdf-font-stream PDF embedded font (sfnt) at offset 0xD5D0 10984 bytes
font_02_sfnt_off0000eed9.bin
ee82a30086b6777ade6483c8f99caaba872a86d7e436ef2c3e73e0799e32fe5e
pdf-font-stream PDF embedded font (sfnt) at offset 0xEED9 20216 bytes