Malicious PDF — malware analysis report

Static analysis result for SHA-256 31864a38ac608ea5…

MALICIOUS

PDF

66.5 KB Created: 2021-09-17 06:16:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 035a328668929c109816011fd677c15a SHA-1: 30d0a2c36de39a12acf794efab2540ff46b071dc SHA-256: 31864a38ac608ea5394d0f18edb48d5054fc2bfa531a82e5b386e61c367ca2fb
124 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains numerous external links, with a high concentration on potentially disposable hosting, indicating a link farm or redirection strategy. Heuristics and ClamAV detection confirm its malicious nature, specifically flagging it as phishing-related. The ML classifier also strongly indicated maliciousness. The primary purpose appears to be directing users to external sites, likely for further exploitation or credential harvesting.

Machine Learning

  • Nyx PDF Classifier malicious score 0.7736

Heuristics 4

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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.
  • 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://catamma.ru/uplcv?utm_term=music+maker+apps+for+android
    • http://www.pes.edu.mn/ckfinder/userfiles/files/lirovul.pdf
    • http://pspectr.ru/userfiles/file/sezazukuwivixe.pdf
    • https://kiofruits.com/admin/uploads/files/46340733275.pdf
    • https://weeb.nu/userfiles/file/27704088087.pdf
    • http://ccspatti.org/userfiles/file/20684313411.pdf
    • http://www.gobarging.com/uploads/textareas/file/39458286841.pdf
    • http://midesignvn.com/uploads/files/wizinewinomuw.pdf
    • http://milwaukee.center/userfiles/file/jinifafukurad.pdf
    • http://boras-sjuharad.boj.se/uploads/userfiles/files/ruwinuwubafusumux.pdf
    • http://groupementpecheduloir.com/ckfinder/userfiles/files/vumitepivelupunoxulinap.pdf
    • http://www.cuadernos.in/wp-content/plugins/formcraft/file-upload/server/content/files/16143f65f96a32---2156023449.pdf
    • http://atek-ent.com/upload/file/vowemov.pdf
    • http://ascensionchina.com/userfiles/file/kipibarar.pdf
    • http://cleangroupbd.com/ck/upload/files/73912445030.pdf
    • https://www.beewellrx.com/wp-content/plugins/super-forms/uploads/php/files/tmp/55606176371.pdf
    • https://grafconsulting.pl/Upload/file/45911877816.pdf
    • https://anzhero-sudzhensk.verlauf-ekb.ru/admin/ckfinder/userfiles/files/galafusegizofugan.pdf
    • http://yuha.be/_files/file/vurojikipinosineb.pdf
    • http://lachambredechos.com/userfiles/file/97255843445.pdf
    • http://fst-uinsu.net/userfiles/files/lixazevewili.pdf
    • http://phongkhamthienhoa.org/images/files/miterawepasotajokokawane.pdf
    • http://kartywspomnien.pl/uploads/assets/file/sarazuvewovepi.pdf
    • http://naosgym.com/userfiles/files/fiwobesesitoped.pdf
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f2cb.bin
a4057c2005cb4e0c33586b46938cc403453f6eef6086411f97a771719e9f1da4
pdf-font-stream PDF embedded font (sfnt) at offset 0xF2CB 10820 bytes