Medium severity · published Jun 18, 2026
CVE-2026-43915
Coturn: Stored Cross-Site Scripting (XSS) in web-admin interface via TURN username
5.4
CVSS
0.2%
EPSS
No
On KEV
Description
Coturn is a free open source implementation of TURN and STUN Server. Versions prior to 4.11.0 contain a stored cross-site scripting (XSS) vulnerability in the web-admin HTTPS interface. An attacker who can create a TURN allocation with a crafted USERNAME value can inject HTML/JavaScript that executes when an authenticated web-admin user views the TURN session list. In configurations using anonymous TURN access (--no-auth), this may be exploitable without TURN credentials. In authenticated deployments, exploitation requires valid TURN credentials or control over a provisioned username. This issue has been fixed in version 4.11.0.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
Required
Confidentiality
Low
Integrity
Low
Availability
None
Scope
Changed
Exploitation
Is it being used?
Exploit prediction (EPSS)0.2% · higher than 15% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
CO
coturn · coturn
< 4.11.0 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-43915
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-43915
Release Notes
https://github.com/coturn/coturn/releases/tag/4.11.0
Vendor Advisory
https://github.com/coturn/coturn/security/advisories/GHSA-xxf5-9vj2-g84j
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