CVE-2026-68553

high
Assigned by CNA: github_m
Published 2026-08-19 · Modified 2026-08-19
CVSS v3
7.1
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:H
CVSS v4 NEW
not yet in upstream
VIR risk
7.1

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.

Predictions

Exploit likelihood
80%
Patch ETA

Heuristic predictions, AS-IS, for prioritization only.

Mitigations

No mitigations published for this CVE yet.

The vendor-content worker queues fetches as references arrive (check back in a few minutes). Or — if you've already worked around this in production — publish your fix to the community-verified tier.

Propose a mitigation on Community Mitigations published via the community go through AI scoring + 2 human reviewers + 7-day silent objection window before landing here with source_tier=community-verified.

References

CWEs

CWE-134

Community-verified mitigations for this CVE will appear above when contributors publish them.

Verify integrity in audit chain (admin only). AS-IS.