CVE-2026-68553

Published: Ago 19, 2026 Last Modified: Ago 19, 2026
ExploitDB:
Other exploit source:
Google Dorks:
HIGH 7,1
Source: [email protected]
Attack Vector: network
Attack Complexity: low
Privileges Required: low
User Interaction: none
Scope: unchanged
Confidentiality: low
Integrity: none
Availability: high

Description

AI Translation Available

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.

134

Use of Externally-Controlled Format String

Draft
Abstraction: Base Structure: Simple
Common Consequences
Security Scopes Affected:
Confidentiality Integrity Availability
Potential Impacts:
Read Memory Modify Memory Execute Unauthorized Code Or Commands
Applicable Platforms
Languages: Not Language-Specific, C, C++, Perl
Likelihood of Exploit: High
View CWE Details
https://github.com/coturn/coturn/commit/8fa38032bb4751e11e0…
https://github.com/coturn/coturn/commit/8fa38032bb4751e11e072d65a8eca3c06c950979
https://github.com/coturn/coturn/releases/tag/4.13.0
https://github.com/coturn/coturn/releases/tag/4.13.0
https://github.com/coturn/coturn/security/advisories/GHSA-4…
https://github.com/coturn/coturn/security/advisories/GHSA-4g7c-p5wg-j4hp