Malicious PDF — malware analysis report

Static analysis result for SHA-256 91358af5c3c5e02f…

MALICIOUS

PDF

62.3 KB Created: 2021-09-22 15:36:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 4c62c0e9b882d6a62771af06ca896fa9 SHA-1: 6e006f632e969490f8c3e75a6167d7d0fc43b532 SHA-256: 91358af5c3c5e02fca90a0758a6c51d5faee478817250ee6dd99c9051166aa98
132 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external links, many of which point to suspicious domains or are structured as link farms. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The embedded JavaScript is a common technique for initiating malicious actions within PDF documents.

Machine Learning

  • Nyx PDF Classifier malicious score 0.5233

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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
  • 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://weboonline.com/ckfinder/userfiles/files/29540129007.pdf
    • http://www.corazondelsol.es/ckfinder/userfiles/files/53707112222.pdf
    • http://statsale.com/data/upload/ck/files/75000297742.pdf
    • https://kclandscapes.com/ckfinder/triplebuserfiles/file/diluvazimubejifunu.pdf
    • https://bibonatura.com/ckfinder/userfiles/files/30692590886.pdf
    • https://profix.fr/ckfinder/userfiles/files/bigubuzojilubedarar.pdf
    • http://ssss-sangam.com/userfiles/file/vatasoxuxatazemuxoravas.pdf
    • https://tramhuonghanoi.vn/upload/files/1095797586.pdf
    • http://palakkadtourism.in/ckfinder/userfiles/files/sorakunumel.pdf
    • http://gospel-pour-100-voix.com/fichiers/newsletter/file/nasudozafedeko.pdf
    • https://navliecky.net/userfiles/file/pigafulevojoza.pdf
    • http://cabanagarden.hu/editor_up/fivusijufazapakuno.pdf
    • https://gtnet-engine.com/ckfinder/userfiles/files/zesikiw.pdf
    • http://trineckevzdelavani.cz/webpagebuilder/ckfinder/userfiles/files/gisuj.pdf
    • http://konakelektrik.com/userfiles/file/mavapabimasajexikiru.pdf
    • http://hourinkan.net/js/upload/files/94993619826.pdf
    • https://thefertilizerproductionline.com/d/files/rugomivodotoxawuviti.pdf
    • https://thokhoavietnam.com/upload/files/6515978117.pdf
    • http://laskod.hu/userfiles/file/soburepevukevi.pdf
    • http://xn--4k0b43gkwo4gn.com/upload/editor/file/voxokomibiduwiwa.pdf
    • http://ednak.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613f490b1b36a---87798200906.pdf
    • https://seas2010.cienciaevida.pt/site/upload/file/bakupenejemuv.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/DOqCt-cVA4I/uplcv?utm_term=enhance+video+quality+free+android
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000c805.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xC805 16792 bytes
font_01_sfnt_off0000e01c.bin
5d923c9dca06cc85565f5990af1c1470efb40f99b452a1bcb9c2f6e1b8685bb9
pdf-font-stream PDF embedded font (sfnt) at offset 0xE01C 10812 bytes