Allocation of Resources Without Limits or Throttling in coTURN - #VU140948
Published: August 5, 2026
Vulnerability identifier: #VU140948
CSH Severity: Medium
CVSS v4: 8.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]
CVE-ID: N/A
CWE-ID: CWE-770
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to cause a denial of service.
The vulnerability exists due to allocation of resources without limits or throttling in the DTLS listener session handling in src/apps/relay/dtls_listener.c when processing initial fragmented ClientHello messages before DTLS cookie validation. A remote attacker can send specially crafted UDP datagrams from fresh source tuples to cause a denial of service.
DTLS must be enabled with a certificate and private key. No TURN credential, completed handshake, valid cookie, source-address spoofing, or response processing is required, and a single host can vary its UDP source port to create distinct tuples.
Affected software
coTURN
Remediation
Install security update from vendor's website.
coTURN - update to 4.16.0