Malicious PDF — malware analysis report

Static analysis result for SHA-256 b7c641fc3d7b6ab4…

MALICIOUS

PDF

72.1 KB Created: 2021-10-01 04:44:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: c47719b32b5bc38d20e200e3794a0469 SHA-1: 44ea4cdc2eaceaeb3d85551adf615b4cf8a2442d SHA-256: b7c641fc3d7b6ab4bd144bc28050e0d69a89c342e8ea85153d2f3dc26f6dc45d
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file contains embedded JavaScript and numerous 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 for phishing or SEO poisoning by redirecting users to malicious sites. The embedded JavaScript is a common technique for executing malicious code or initiating redirects within PDF documents.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9902

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://wastran.ru/uplcv?utm_term=malayalam+pranaya+kavithakal+mp3+free+download
    • https://autotrilogy.com/wp-content/plugins/super-forms/uploads/php/files/fd841502fd5af4768ec15a508f13a5bb/38402776200.pdf
    • http://goodtraefarm.com/ckupload/files/fidazabedor.pdf
    • http://na3.it/misc/file/11224796438.pdf
    • http://puebloexec.com/userfiles/file/medalen.pdf
    • http://imosa.asia/uploads/files/202109140704572792.pdf
    • https://intelean.com/wp-content/plugins/formcraft/file-upload/server/content/files/161308ec84f7b5---4559167847.pdf
    • http://www.juniorcollege.cl/ckfinder/userfiles/files/lezomodut.pdf
    • http://andreevka.topmebli.com/content/xuploadimages/file/jigezogesosofetelirub.pdf
    • http://counterreaction.net/wp-content/plugins/formcraft/file-upload/server/content/files/1613fa199c4e72---takalelujajisagux.pdf
    • http://jevades.com/aircraft/fckimages/file/pemipukewulaxipozowuxajik.pdf
    • https://egyediajandekotletek.hu/mvc/userfiles/file/zavusinexejexilavibasoxel.pdf
    • http://coaching-scolaire.net/userfiles/file/79307689506.pdf
    • http://www.szphotar.com/admin/img/files/63148120236.pdf
    • https://nazrabilisim.com/calisma2/files/uploads/4194285360.pdf
    • http://businessvaluationapp.com/fck_files/file/jexosarozekovoxosir.pdf
    • http://garageanything.com/js/upload/files/1123352174.pdf
    • http://sarkar.ie/userfiles/file/wavabonolexi.pdf
    • http://dj-maily.com/uploads/pages/files/doxemajusezu.pdf
    • http://la-roofers.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/161311207028cc---jejiveselizevu.pdf
    • http://bjjiffy.com/upload/sebenez.pdf
    • http://kazuma.ru/ckfinder/userfiles/files/50608831871.pdf
    • https://china-glass-mosaic.vegner.com/userfiles/files/20210913_103528.pdf
    • https://congchunghadong.com/uploads/files/55924551235.pdf
    • https://yenicekentkaplicasi.com/userfiles/file/26161262008.pdf
    • http://goldsunjsc.com/upload/files/vegexawufiwevatowolog.pdf
    • https://elitstroycraft.ru/source/file/33652193082.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_off0000b560.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xB560 16792 bytes
font_01_sfnt_off0000cd77.bin
d1a318b05ecd18ae379d47929e6245a77c4705451674fcbb8f3c0800df217787
pdf-font-stream PDF embedded font (sfnt) at offset 0xCD77 11116 bytes
font_02_sfnt_off0000e741.bin
df1de27a74cbfa3d9a471aa4fd6035b7de68578ac7c7500233df768bbe0103b8
pdf-font-stream PDF embedded font (sfnt) at offset 0xE741 15972 bytes