Malicious PDF — malware analysis report

Static analysis result for SHA-256 764311d41f8a6ea2…

MALICIOUS

PDF

81.9 KB Created: 2021-08-12 09:34:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 73d1c8be3c9a6bae7d231c2a6552b8a2 SHA-1: 1a19cc3cde663ba63f13d8ffac214b7c13528406 SHA-256: 764311d41f8a6ea2154e6f2298999c91566a316054bb4c0d6c488db702742fde
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript, a common technique for executing malicious code within documents. It also features a link farm pointing to multiple distinct hosts, many of which appear to be compromised CMS installations or disposable hosting, suggesting an attempt to obscure the final destination. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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://www.andyselfstorage.co.uk/wp-content/plugins/super-forms/uploads/php/files/nc0boo59rkijol8ita4lkbhh8b/kujipobarodiliguxizaw.pdf
    • http://dom-2000.ru/ckfinder/userfiles/files/29391004718.pdf
    • http://clarksville.net/wysiwygfiles/file/tukalavitubusi.pdf
    • https://pezenasenchantee.fr/userfiles/file/fitijefuvoruwotelad.pdf
    • https://genesislighting.net/wp-content/plugins/super-forms/uploads/php/files/076b1a3df7046ad0219f51e33cf84b96/xitalof.pdf
    • http://www.jfac.kr/ckfinder/userfiles/files/duwarukuserar.pdf
    • http://www.kissdocs.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1608688cdaa056---53287920966.pdf
    • http://tfh-filter.hu/_user/file/kegamek.pdf
    • http://wohingltd.com/userfiles/lijido.pdf
    • https://skazkavdom.com/wp-content/plugins/super-forms/uploads/php/files/aff506b48bcdb1f0743e05dea872da2a/turiratapepise.pdf
    • http://learnazia.com/fck/imagesfile/vepukivube.pdf
    • https://ercrs.org/wp-content/plugins/super-forms/uploads/php/files/55b3spha1c9tnq8kf69cp5vb4k/xubif.pdf
    • http://www.sunarmisir.com.tr/wp-content/plugins/super-forms/uploads/php/files/c98js5oa5hiil4j1rac7d7clk1/34569695540.pdf
    • https://nowackleverkusen.de/wp-content/plugins/formcraft/file-upload/server/content/files/160bdfbd4cbbea---tuzomajatarokunofodamasaz.pdf
    • http://nagakuratrading.com/js/upload/files/96234998522.pdf
    • http://automsystem.com/UploadFile/file/20210803150502889.pdf
    • https://www.kiakaha.gr/wp-content/plugins/super-forms/uploads/php/files/lguiudvof33esaahs6eolvd8qq/77743655238.pdf
    • http://takeacode.net/user/d41d8cd98f00b204e9800998ecf8427e/file/kojowadoju.pdf
    • https://www.dolphinrfid.com/wp-content/plugins/formcraft/file-upload/server/content/files/160892d174477f---40593631578.pdf
    • https://langumeistras.lt/i/File/86180606636.pdf
    • http://riggi.ru/userfiles/file/pelilevirituwoxazot.pdf
    • https://www.chortho.co.uk/wp-content/plugins/super-forms/uploads/php/files/4mjm5bm68emrsu76lh6gerdtsa/54203387955.pdf
    • http://hintzfamilyreunion.com/clients/1/12/12a2788c5de59b93c87e4eff35998d4f/File/fasimisiforer.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/BkSY9tpko7c/uplcv?utm_term=vw+caddy+motability+price+list+2020
    • 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_off0000db38.bin
d06227a171f303f9d96dfad9091115c46a6dcdb4b5d4416d1d2194f3381fea1d
pdf-font-stream PDF embedded font (sfnt) at offset 0xDB38 17224 bytes
font_01_sfnt_off000107c8.bin
234291f778cccc7d273557843fb0f6aab7ba5cd1c83b1404a7a35cc5ff24c260
pdf-font-stream PDF embedded font (sfnt) at offset 0x107C8 11124 bytes
font_02_sfnt_off000121ac.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x121AC 16792 bytes