CVE-2026-73259 (GCVE-0-2026-73259)

Vulnerability from cvelistv5 – Published: 2026-08-20 17:39 – Updated: 2026-08-20 19:51
VLAI
Title
Mongoose: Reflected XSS via decoded URI in directory listing render
Summary
Mongoose is an embedded web server and network library. Prior to 7.22, a remote attacker can send a crafted percent-encoded request path to a deployment using MG_ENABLE_DIRLIST and persuade a user to visit it. The mg_http_serve_dir() and listdir() path in src/http.c places the decoded request URI into the title and h1 elements without HTML entity encoding. The resulting reflected cross-site scripting executes in the Mongoose origin and can expose session data or perform actions as the victim. This issue is fixed in version 7.22.
Severity
5.4 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N
SSVC
Exploitation: poc Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-20 19:50 UTC
CWE
  • CWE-79 - Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 7634 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
cesanta mongoose Affected: < 7.22
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

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