Malicious PDF — malware analysis report

Static analysis result for SHA-256 cf8b3370d36d0afb…

MALICIOUS

PDF

92.3 KB Created: 2021-07-06 15:21:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: f58c70de41d3dbfca805cb9a48d6c011 SHA-1: bce33cc63302acd20e56a031e049edad1c40395f SHA-256: cf8b3370d36d0afbfb975c971ffe2344d9f48ca390af384344350daa21b34982
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 websites or disposable hosting, indicating a link farm designed to redirect users. The ClamAV detection and ML classifier strongly suggest malicious intent, likely related to phishing or distributing further malware. The embedded JavaScript is a common technique for exploiting PDF vulnerabilities or initiating malicious actions.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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://crysiq.ru/uplcv?utm_term=if+you+want+to+make+the+world+a+better+place+take+a+look+at+yourself+and+make+a+change
    • https://kachhiproperties.com/wp-content/plugins/super-forms/uploads/php/files/6rsqi8jm64c1jo54uhfoefjqb7/ninejogezepupovajo.pdf
    • http://taiwanglassgroup.cn/userfiles/file/33634170845.pdf
    • http://lindseyderence.com/userfiles/files/bixabesewukexol.pdf
    • http://www.ponderosafestival.com/wp-content/plugins/formcraft/file-upload/server/content/files/16091363d80b08---rudumakasaz.pdf
    • https://www.straightmyteeth.eu/wp-content/plugins/super-forms/uploads/php/files/38d7ae3dc8215da30348cabb03c39d46/12341863391.pdf
    • http://ctyrkolky-gamax.cz/data/dokumenty/50784229327.pdf
    • http://bristolvietnam.com/upload/ck/files/lepunaz.pdf
    • http://berbun.com/user_img/file/66416690829.pdf
    • http://bjjiffy.com/upload/dofifapuwit.pdf
    • https://paymentor.nl/uploads//file/jirosuvow.pdf
    • https://espaciocultivarte.com/ckfinder/userfiles/files/62306678577.pdf
    • https://planet-for-events.de/userfiles/file/zolojapazufizupabepivirow.pdf
    • https://leunamgroup.com/wp-content/plugins/super-forms/uploads/php/files/08e2262b27a565181b9200a1af1e4d8a/loxepumadonojina.pdf
    • http://elonsummerstorage.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b9e2690302a---bebijegubofudizu.pdf
    • http://ms-krmelin.cz/app/webroot/files/files/lotelimeji.pdf
    • http://www.kissdocs.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160d93399d4d84---8176544805.pdf
    • https://fnb-concepts.com/images/uploads/files/93051899395.pdf
    • http://due.pt/js/ckfinder/userfiles/files/71951418363.pdf
    • https://sipare.com.ar/wp-content/plugins/super-forms/uploads/php/files/sr35m56brl1febmlpafro1bb1p/dafosivejota.pdf
    • http://churchliferesources.org/wp-content/plugins/formcraft/file-upload/server/content/files/160c972466a718---90368644027.pdf
    • https://cursosgratuitosonline.es/wp-content/plugins/super-forms/uploads/php/files/u8c3q3grm3asu2n2skbmlharev/82939928179.pdf
    • https://israelonthehouse.com/wp-content/plugins/formcraft/file-upload/server/content/files/160817d8be7393---wimakiw.pdf
    • http://reclaimsplus.com/wp-content/plugins/super-forms/uploads/php/files/c7d9714a132a4db10a9695187938a70b/nazusedapurawekuborivik.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_off00010567.bin
1cb3b7805fd3e56a3a105bb8cd39eaede13f17d3b866995379b9a141e99f6646
pdf-font-stream PDF embedded font (sfnt) at offset 0x10567 11456 bytes
font_01_sfnt_off00011fea.bin
c04b4042eeeea5ab7b5f73edebdd600143357bb02d6bfd96228854de47901d56
pdf-font-stream PDF embedded font (sfnt) at offset 0x11FEA 16612 bytes
font_02_sfnt_off00014b1d.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x14B1D 16792 bytes