Malicious PDF — malware analysis report

Static analysis result for SHA-256 40b289235138a2ba…

MALICIOUS

PDF

82.0 KB Created: 2021-09-17 11:48:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: f6ee71c224020ba28e6997942681c52f SHA-1: cbd2d9132b622951ceda8288212766e57158b981 SHA-256: 40b289235138a2ba55b7c36fd174a57c6332280f53746074e8f06b94fff4f2db
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 or disposable hosting. These elements suggest the document is designed to act as a link farm, redirecting users to external sites for malicious purposes such as phishing or malware downloads. The ML classifier and ClamAV detection strongly indicate malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9846

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://ketchas.ru/uplcv?utm_term=best+hacked+games+apk
    • http://liily.jp/upload/file/20210906135259.pdf
    • http://gamecoast.by/uploads/files/99057217840.pdf
    • http://freehajjandumrah.com/admin/admin/uploadfiles/file/jakowifewopobowekujinor.pdf
    • http://jinwoosmc.com/userfiles/file/50927860151.pdf
    • http://ramseier-appenzell.ch/elrada/js/ckfinder/userfiles/files/64190363705.pdf
    • https://detmers-kontejner.hr/files/12182770823.pdf
    • http://holland-ex.com/images/blog/file/36893764803.pdf
    • http://elcampoeco.org/FCKeditor/file/lalexitokutol.pdf
    • https://xn--90ah6akb9e.xn--p1ai/f/file/66449075087.pdf
    • http://xsteelstock.com/d/files/gewalofa.pdf
    • http://milcontabil.com.br/wp-content/plugins/super-forms/uploads/php/files/ur7jg1b0jsrmp6mc00020sp0d4/gavababepukadukete.pdf
    • https://giant-nano.com/app/webroot/userfiles/files/30833900772.pdf
    • http://library.nesdb.go.th/ic/admin/ckfinder/userfiles/files/mefejofu.pdf
    • http://vibrosystem.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1612f96bd6f342---xuveli.pdf
    • http://anabakorea.jp/userfiles/file/jidutefig.pdf
    • http://katela.net/userData/board/file/memigos.pdf
    • http://budropol.de/Upload/file/pufafulobunizenonisunabux.pdf
    • https://pet-fashion.ro/mm/file/79858749466.pdf
    • http://rlponder.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/35105051107.pdf
    • http://sieuthivatlieuhoanthien.com/upload/files/ribar.pdf
    • http://nhactheducthammy.com/upload/files/vadixeda.pdf
    • https://camile.vn/wp-content/plugins/super-forms/uploads/php/files/e0ilh9hngbe99fmpovnd5h12m5/gakadagikewubapokul.pdf
    • http://spellenindex.nl/images/uploads/zozejaziralaguw.pdf
    • http://www.sunarpazarlama.com/wp-content/plugins/super-forms/uploads/php/files/98uppfcsnvmv3if859ov027gv3/zupibubefezipukemob.pdf
    • http://k12kos.com/ckfinder/userfiles/files/lironalesiriwuzu.pdf
    • http://kystop.com/wp-content/plugins/super-forms/uploads/php/files/93b13c8a4e1ca8e3a8abb7767c02200a/xatukutorajuvega.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_off0000dbfe.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xDBFE 16792 bytes
font_01_sfnt_off0000f410.bin
08d6564c3525a5e06d18621c1734f6abd20c761c3fdb73005d9074c8b948ae65
pdf-font-stream PDF embedded font (sfnt) at offset 0xF410 17712 bytes
font_02_sfnt_off0001226c.bin
55e0c71f83d6ea2da5160d7954993e9d2980d7361ac25006bdfb881e3fc8ec98
pdf-font-stream PDF embedded font (sfnt) at offset 0x1226C 10644 bytes