CVE-2026-73254 (GCVE-0-2026-73254)

Vulnerability from cvelistv5 – Published: 2026-08-20 17:37 – Updated: 2026-08-21 16:22
VLAI
Title
Mongoose: Stored XSS via unescaped filenames in directory listing
Summary
Mongoose is an embedded web server and network library. Prior to 7.22, an attacker who can create a file with an HTML payload in its name can trigger stored cross-site scripting when a user browses a directory served with MG_ENABLE_DIRLIST. The printdirentry() path called by listdir() in src/http.c URL-encodes the href but inserts the raw filesystem filename into the HTML link text. The browser executes the injected markup in the Mongoose origin, which can expose session data or permit 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 2026-08-21 16:21 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 7640 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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