Upstream information
Description
Coturn is a free open source implementation of TURN and STUN Server. Prior to 4.13.0, coturn rejects loopback peers by default unless allow-loopback-peers is enabled, but the default loopback guard can be bypassed by using the IPv4-mapped IPv6 peer address ::ffff:127.0.0.1 in a TURN XOR-PEER-ADDRESS attribute. ioa_addr_is_loopback checks for the literal IPv6 loopback shape before IPv4-mapped IPv6 handling, so good_peer_addr does not apply the default loopback rejection and an authenticated TURN client can expose services bound only to localhost on the coturn host through TURN relay traffic. This issue is fixed in version 4.13.0.SUSE information
Overall state of this security issue: Does not affect SUSE products
This issue is currently rated as having important severity.
| CVSS detail | CNA (GitHub) | SUSE |
|---|---|---|
| Base Score | 7.4 | 7.4 |
| Vector | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:L | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:L |
| Attack Vector | Network | Network |
| Attack Complexity | Low | Low |
| Privileges Required | Low | Low |
| User Interaction | None | None |
| Scope | Changed | Changed |
| Confidentiality Impact | Low | Low |
| Integrity Impact | Low | Low |
| Availability Impact | Low | Low |
| CVSSv3 Version | 3.1 | 3.1 |
| CVSS detail | SUSE |
|---|---|
| Base Score | 5.3 |
| Vector | CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N |
| Attack Vector | Network |
| Attack Complexity | Low |
| Attack Requirements | None |
| Privileges Required | Low |
| User Interaction | None |
| Vulnerable System Confidentiality Impact | Low |
| Vulnerable System Integrity Impact | Low |
| Vulnerable System Availability Impact | Low |
| Subsequent System Confidentiality Impact | None |
| Subsequent System Integrity Impact | None |
| Subsequent System Availability Impact | None |
| CVSSv4 Version | 4.0 |
SUSE Timeline for this CVE
CVE page created: Mon Jul 13 15:29:20 2026CVE page last modified: Mon Jul 13 19:32:07 2026