Malicious PDF — malware analysis report

Static analysis result for SHA-256 cf38f04785eacdb3…

MALICIOUS

PDF

82.4 KB Created: 2021-09-17 08:20:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: e670142f2dd6c4e657d68a15573a8836 SHA-1: 0f0379bb93e0120be135462c9c8d7192580e276c SHA-256: cf38f04785eacdb38675d5a1229e32733971bf857b3a7afdff8c8ce24c386158
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF containing embedded JavaScript and numerous external links, many of which point to compromised WordPress sites or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The embedded JavaScript and link farm structure suggest an attempt to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.opdrrustukalac.com/wp-content/plugins/formcraft/file-upload/server/content/files/16137435bacb8e---20915875478.pdf
    • https://lolakarimova.uz/ckfinder/userfiles/files/17310413893.pdf
    • https://www.abandassociates.com/ckfinder/userfiles/files/3295555836.pdf
    • http://minuspk.ru/minuspk.ru/userfiles/file/67897723858.pdf
    • https://campermagazine.tv/public/file/vozetapixubo.pdf
    • http://cetis156.neutronds.com/assets/js/ckfinder/userfiles/files/nikerojubavoj.pdf
    • http://master-br.ru/img/file/25346269108.pdf
    • https://newshieldinsurance.com/demo/gsa/final/images/file/divolozexaguxazafe.pdf
    • https://b2cexpressdemo.com/userfiles/file/46168736833.pdf
    • https://vetregistr.com/ckfinder/userfiles/files/simadadafaxaparuvo.pdf
    • http://uptownherndon.com/uploads/files/wafuxif.pdf
    • http://gaia-onlus.org/userfiles/file/11165450645.pdf
    • http://kriosispl.com/cote_dor_import/admin/ckfinder/userfiles/files/duwowegit.pdf
    • https://pachetedeturism.ro/images/files/jifarojorojoxovamoxu.pdf
    • https://tckontrola.hr/files/10524650744.pdf
    • http://dakmoto.cz/obrazky/file/xufodeduxonufosol.pdf
    • http://3bbb.fr/ckeditor/upload/files/povasisuwerabava.pdf
    • https://euforbiabulgaria.com/uploads/pages/files/3104202957.pdf
    • https://bilegt.mn/userfiles/files/vuwadagazarukikusararovux.pdf
    • https://goactive.hu/wp-content/plugins/super-forms/uploads/php/files/81abfda5ec2e45fc70abadb3b595ccc0/vunegukomudumefadowa.pdf
    • https://www.sblending.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1612f857488cdb---xijimididurijuzupeli.pdf
    • http://aktifithalat.com/resimlerfiles/816539291.pdf
    • https://queensflower.nl/clientfiles/sonewutufum.pdf
    • http://sahcarpets.com/userfiles/file/popojojawimutu.pdf
    • http://hanboo.cn/Uploads/file/2021090504331670554.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/GLLx1DTH0VQ/uplcv?utm_term=best+android+apps+for+hacking+wifi+password
    • 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_off0000db0b.bin
95d9dbcbeae5cc4762b398ae00151abcdd633527578a96733b530e61d5c99748
pdf-font-stream PDF embedded font (sfnt) at offset 0xDB0B 17380 bytes
font_01_sfnt_off0001080f.bin
67dec0d8eca4db8999babcf0c9d2bdbe891249c5f5a91bc5eec2847d2653e072
pdf-font-stream PDF embedded font (sfnt) at offset 0x1080F 11084 bytes
font_02_sfnt_off000121c6.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x121C6 16792 bytes