Upstream information
Description
Coturn is a free open source implementation of TURN and STUN Server. Prior to 4.13.0, an authenticated TURN user can place printf-style format specifiers in the STUN USERNAME or REALM attribute, which passes is_secure_string() validation and is embedded into Redis keys at nine call sites in src/apps/relay/ns_ioalib_engine_impl.c. send_message_to_redis() in src/apps/relay/hiredis_libevent2.c then passes the attacker-controlled key as the format argument to redisAsyncCommand() while supplying only one variadic value, causing hiredis redisvFormatCommand() to read past the va_list. Exploitation can crash the coturn process and terminate active TURN sessions or disclose stack memory into Redis. This issue is fixed in version 4.13.0.SUSE information
Overall state of this security issue: Revisit
This issue is currently rated as having important severity.
| CVSS detail | CNA (GitHub) |
|---|---|
| Base Score | 7.1 |
| Vector | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:H |
| Attack Vector | Network |
| Attack Complexity | Low |
| Privileges Required | Low |
| User Interaction | None |
| Scope | Unchanged |
| Confidentiality Impact | Low |
| Integrity Impact | None |
| Availability Impact | High |
| CVSSv3 Version | 3.1 |
SUSE Timeline for this CVE
CVE page created: Thu Aug 20 21:15:03 2026CVE page last modified: Sat Aug 22 11:40:27 2026