CVE-2026-43915 Coturn: Stored Cross-Site Scripting (XSS) in web-admin interface via TURN username
An attacker can inject malicious scripts into the Coturn web-admin interface via TURN usernames, potentially compromising admin sessions.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- Available
What is CVE-2026-43915?
CVE-2026-43915 is a medium-severity cross-site scripting vulnerability in coturn, published on 18 Jun 2026. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link.
Official 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.
Weakness: CWE-79
Which versions are affected by CVE-2026-43915?
It affects 1 product.
Products include Coturn Project Coturn.
How do I fix CVE-2026-43915?
Upgrade to a fixed version.
Escape output for the context it lands in and set a strict Content Security Policy. Upgrading the affected component is the real fix. More about Cross-site scripting.
Is CVE-2026-43915 being exploited?
There is no known exploitation of CVE-2026-43915 in the wild and no public exploit code.
Other vulnerabilities in coturn
- CVE-2018-4056 SQL injection in coTURN
- CVE-2026-43994 Coturn: Stack buffer overflow in decode_oauth_token_gcm()
- CVE-2018-4058 Server-side request forgery in coTURN
- CVE-2026-40613 Coturn: Misaligned Memory Access in coturn STUN Attribute Parser (Remote DoS on ARM64)
- CVE-2026-53450 Coturn: IPv4-mapped 127.0.0.1 bypasses default loopback peer protection
Sources
Also known as DEBIAN-CVE-2026-43915, GHSA-xxf5-9vj2-g84j, UBUNTU-CVE-2026-43915.