Description
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.
Published: 2026-08-20
Score: 5.4 Medium
EPSS: n/a
KEV: No
Impact: n/a
Action: n/a
AI Analysis

No analysis available yet.

Remediation

No remediation available yet.

Tracking

Sign in to view the affected projects.

Advisories

No advisories yet.

History

Thu, 20 Aug 2026 18:45:00 +0000

Type Values Removed Values Added
First Time appeared Cesanta
Cesanta mongoose
Vendors & Products Cesanta
Cesanta mongoose

Thu, 20 Aug 2026 17:45:00 +0000

Type Values Removed Values Added
Description 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.
Title Mongoose: Stored XSS via unescaped filenames in directory listing
Weaknesses CWE-79
References
Metrics cvssV3_1

{'score': 5.4, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N'}


Subscriptions

Cesanta Mongoose
cve-icon MITRE

Status: PUBLISHED

Assigner: GitHub_M

Published:

Updated: 2026-08-20T17:37:17.245Z

Reserved: 2026-08-11T17:18:01.598Z

Link: CVE-2026-73254

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Received

Published: 2026-08-20T18:16:46.113

Modified: 2026-08-20T18:16:46.113

Link: CVE-2026-73254

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-08-20T18:30:03Z

Weaknesses
  • CWE-79

    Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')