Malicious PDF — malware analysis report

Static analysis result for SHA-256 496a6ca7a92f5ecb…

MALICIOUS

PDF

70.0 KB Created: 2021-10-09 16:44:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 8c2cde434b083868063d7bb1a41273fa SHA-1: b65ca9b2b15ab689c640e2ad7dd3440b55a892dc SHA-256: 496a6ca7a92f5ecb8f1eebdcb89dfabf9975e8ae20f907b5648feb46ad7ffc94
164 Risk Score

Malware Insights

MITRE ATT&CK
T1203 Exploitation for Client Execution

The PDF contains embedded JavaScript and multiple external URIs, many of which point to compromised CMS upload directories or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to exploit a PDF vulnerability for client-side execution and download of a secondary payload. The presence of a link farm on potentially compromised or disposable hosting further supports this.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9916

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://mackielaw.net/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/lelatuzirexojub.pdf
    • https://personalloan2u.com/wp-content/plugins/super-forms/uploads/php/files/79609101e99b041c8fd4e122b59cfd4d/76828765555.pdf
    • http://www.jesuseslaroca.org/wp-content/plugins/formcraft/file-upload/server/content/files/16159fd64a048e---57158754124.pdf
    • http://everestlodgelukla.com/userfiles/file/mogasuvufa.pdf
    • https://viajespereira.com/wp-content/plugins/formcraft/file-upload/server/content/files/16144649daf208---22032157298.pdf
    • http://disonde.com/filespath/files/20210925082138.pdf
    • http://gaishachuukobuhin.com/js/upload/files/kubep.pdf
    • https://pbanerjeeservices.4digitmagic.com/userfiles/file/dikon.pdf
    • http://iact2001.com/userData/board/file/jimomofajuwazimifaxaf.pdf
    • http://arserwood.com/js/fckeditor/editor/filemanager/connectors/php/connector.php/upfiles/file/210911025409893151akxtgw.pdf
    • https://inprovitecuador.com/ckfinder/userfiles/files/17930071121.pdf
    • https://insolite.lu/img/userfiles/files/48652382882.pdf
    • https://www.truesdalepainting.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613bbab2c273e---lipaxenewovokidagufe.pdf
    • https://lrsinc.co/userfiles/file/zuponanamox.pdf
    • https://bolahijau.com/contents/files/55602882638.pdf
    • http://gzcil.com/uploadfile/files/84847276133.pdf
    • http://www.hcibatiment.fr/wp-content/plugins/formcraft/file-upload/server/content/files/16139cd36ec992---17332981874.pdf
    • http://www.themixchange.com/userfiles/files/kukiburezanixopilozifaf.pdf
    • http://zaiger.ru/img/file/wiladukojetubivadaleno.pdf
    • http://keystoparadise.com/userfiles/files/80908336011.pdf
    • http://27derajat.com/assets/ckfinder/core/connector/php/uploads/files/67468702848.pdf
    • http://giasudaihocsupham.com/Images_upload/files/16724533673.pdf
    • https://krafteco.ru/uploads/files/67422062355.pdf
    • http://flightshop.jp/images/blog/file/mugixibe.pdf
    • https://nbcmedia.vn/ckfinder/userfiles/files/16852612026.pdf
    • http://nhatrangpalace.net/app/webroot/upload/files/89028683868.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/ngfLrbzwjls/uplcv?utm_term=brain+waves+for+learning
    • 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_off0000b578.bin
2643a7a828e671685bc1c5812fdfe57654ca893714227647f19273ff570275fe
pdf-font-stream PDF embedded font (sfnt) at offset 0xB578 14524 bytes
font_01_sfnt_off0000d9ed.bin
5c9e84622309d4c612b3c5e36da99729929bf38f24164546b5592e07b035dd00
pdf-font-stream PDF embedded font (sfnt) at offset 0xD9ED 10496 bytes
font_02_sfnt_off0000f1fc.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF1FC 16792 bytes