Malicious PDF — malware analysis report

Static analysis result for SHA-256 f635a4b237c879d4…

MALICIOUS

PDF

79.5 KB Created: 2021-07-28 14:52:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 81d99a2cd3096fbc3de9b8fbeb75a0f4 SHA-1: 8b86086f07633ce99f2221b0bcc2cacfed624a1d SHA-256: f635a4b237c879d47554f9d49f34fed1c4b87dd92609ea9a900b8d915180d96d
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF contains embedded JavaScript, which is a common technique for executing malicious code. The PDF also features a link farm pointing to multiple distinct hosts, many of which are hosted on disposable domains or compromised CMS upload storage, suggesting an attempt to obscure the final malicious destination. The ClamAV detection and ML classifier strongly indicate malicious intent, likely for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9987

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 http://donationwebsites.com/clients/6/68/68901b9e08e997a22fc64c74502b39ca/File/kelixojarutefuba.pdf
    • https://ailani.org/wp-content/plugins/super-forms/uploads/php/files/7fee69156daabb0022a88096e4e3e1fb/taramofijurijukepifovi.pdf
    • http://homenet-spb.ru/userfiles/file/66356273382.pdf
    • http://vuadiemtayninh.com/hinhanh_fckeditor/file/mepodulaguvegimamedasir.pdf
    • https://immobilgold.com/file/letenep.pdf
    • http://alnoorcity.com/userfiles/file/mariko.pdf
    • http://aa-nusd.jp/wafezolawelireve.pdf
    • http://dlmberatung.ch/userfiles/files/boxazimigitefumusew.pdf
    • http://fillaracingacademy.cz/ckfinder/userfiles/files/68773391254.pdf
    • https://creativesilhouettes.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1607cb702043c2---bejokujijixadavugibug.pdf
    • http://www.associatedomains.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608b32dbb4cee---75645856183.pdf
    • https://nikken-engineer.jp/export/sd205/www/jp/r/e/gmoserver/8/6/sd0748886/nikken-engineer.jp/fckeditor/upload/file/viled.pdf
    • http://simkoongschool.com/uploads/editer/files/lobopopuwovozo.pdf
    • http://ues-rb.ru/themes/ues-rb.ru/files/60243598502.pdf
    • http://www.zopfitravel.com/wp-content/plugins/formcraft/file-upload/server/content/files/16080e9fa2653d---69213153549.pdf
    • http://thementalhealthadvocates.org/files/userfiles/file/29701883803.pdf
    • https://www.cr-sdc.org/wp-content/plugins/super-forms/uploads/php/files/be586806c8f63fddd193836e8754cc67/xupemodamomolerer.pdf
    • https://sportcity.bg/webroot/img/content/files/40260929390.pdf
    • http://integrotech.com/zdjecia/file/97513762419.pdf
    • http://dragoniresorts.com/userfiles/gevipuveputonatifogolol.pdf
    • http://claudiodauelsberg.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160726d1578bfc---52321335163.pdf
    • http://finalstage.biz/js/upload/files/pumixuzogibetoxovaj.pdf
    • http://www.cuerpomenteyespiritu.es/wp-content/plugins/formcraft/file-upload/server/content/files/160a3da9a09b39---dudet.pdf
    • http://www.nanodrywash.com/wp-content/plugins/formcraft/file-upload/server/content/files/16092b73b9a5c3---xajifesuvurumikitogugebem.pdf
    • http://kyanite.tv/userfiles/file/59852990784.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1xuhb7AK25c/uplcv?utm_term=earn+to+die+unblocked+games+2012
    • 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_off0000d3d0.bin
692b1ee37136e0e916552367c4995e8777e62285d5f42c2c33e8cd2bef12c178
pdf-font-stream PDF embedded font (sfnt) at offset 0xD3D0 16056 bytes
font_01_sfnt_off0000fd2b.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xFD2B 16792 bytes
font_02_sfnt_off00011542.bin
021ad046b0d57cf21b4272d9290b32dc60cf43bfcac6852c023375631a0a3ae1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11542 11324 bytes