Malicious PDF — malware analysis report

Static analysis result for SHA-256 8c0a615dba6037cf…

MALICIOUS

PDF

80.0 KB Created: 2021-09-12 18:54:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 4cf9f4d0728007287c94d917f476a8c8 SHA-1: 03450048558c7901b2d838322d304728e4beeec8 SHA-256: 8c0a615dba6037cf8ef61e3b0978bfa4ce92a8c5374518d533cac85f219cca09
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external URIs, many of which point to compromised WordPress sites or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. The embedded JavaScript is a common technique for initiating malicious actions within PDFs.

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://hylyt.co/wp-content/plugins/super-forms/uploads/php/files/e8f786709d3470399308a385b143f5b5/19843320406.pdf
    • http://vstarmp.cn/upload/files/20210901_121430.pdf
    • http://ressourcengarten.de/azubi/userfiles/files/lixodekoraraze.pdf
    • http://www.buildonhope.org/file/kedabegiruragevurifelelo.pdf
    • http://squarcialupirelaxinchianti.com/writable/public/userfiles/file/xetenewikuji.pdf
    • http://www.louisianarebarcontractor.com/editorimg/file/dogosixifumap.pdf
    • http://craft-personal.de/userfiles/file/39523829169.pdf
    • http://www.absolutecateringla.com/wp-content/plugins/formcraft/file-upload/server/content/files/16131f454c77c4---70066695860.pdf
    • https://debcopharma.com/userfiles/file/7862775628.pdf
    • http://geriatriccarenewjersey.com/userfiles/files/70053207537.pdf
    • http://kfnmdg.com/upfolder/e/files/20210912071946.pdf
    • http://biurod9.pl/public/userfiles/file/43305530826.pdf
    • http://xinchenfast.com/upload/file/23735724659.pdf
    • https://uleshuzataruhaz.hu/files/file/dokutifijajiliwulemixa.pdf
    • http://pcccphucvinh.com/upload/files/rudodixojasunuzolosepubi.pdf
    • https://komunalno-vrgorac.hr/files/96043794056.pdf
    • http://pes.edu.mn/ckfinder/userfiles/files/88162077255.pdf
    • http://odontotecnicacoop.it/userfiles/file/17060107808.pdf
    • http://www.ernakulamarchdiocese.org/www/js/ckfinder/userfiles/files/ruvifoge.pdf
    • http://www.sunarsurdurulebilir.com/wp-content/plugins/super-forms/uploads/php/files/sqs8o1dk7ucu0jmi7ipqbv2de1/xaxinetazigek.pdf
    • https://paradigma.bg/uf/file/13221517863.pdf
    • http://zensushialiso.com/uploads/files/73330337490.pdf
    • http://gyn-ordi.at/myPix/file/tuwudabirepatasabokigar.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/ngfLrbzwjls/uplcv?utm_term=repost+instagram+pro+apk
    • 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_off0000d27a.bin
007f11d9b4d4a51c192c77a249524aecb5d63460926d78633b7940e7df1a9c37
pdf-font-stream PDF embedded font (sfnt) at offset 0xD27A 17884 bytes
font_01_sfnt_off0001016f.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1016F 16792 bytes
font_02_sfnt_off00011986.bin
929bce1a0407e8aac8e5a8e9dec4dd21db0f368c430ff19e7763932647c96c1d
pdf-font-stream PDF embedded font (sfnt) at offset 0x11986 10684 bytes