CVE-2026-68555 (GCVE-0-2026-68555)
Vulnerability from cvelistv5 – Published: 2026-08-19 20:43 – Updated: 2026-08-21 18:14
VLAI
EPSS
VEX
Title
coturn: Chained mobility resumes allow authenticated remote memory exhaustion
Summary
Coturn is a free open source implementation of TURN and STUN Server. In 4.15.0, an authenticated TURN user can repeatedly resume one allocation from fresh UDP 5-tuples without completing a handoff when the server enables --mobility. mobile_begin_transition() in src/server/ns_turn_server.c disarms each new session's allocation timeout and overwrites the allocation's single mobile_pending_resume link, leaving earlier pending sessions unreachable by the cleanup path, while copy_auth_parameters() ignores inc_quota() failure. The attacker can therefore retain unbounded server-side sessions and exhaust process memory even when --user-quota=1 is configured. This issue is fixed in version 4.16.0.
Severity
6.5 (Medium)
SSVC
Exploitation: poc
Automatable: no
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-21 18:13 UTC
CWE
- CWE-400 - Uncontrolled Resource Consumption
Assigner
References
3 references
| URL | Tags |
|---|---|
| https://github.com/coturn/coturn/security/advisor… | x_refsource_CONFIRM |
| https://github.com/coturn/coturn/commit/a97f1924b… | x_refsource_MISC |
| https://github.com/coturn/coturn/releases/tag/4.16.0 | x_refsource_MISC |
Impacted products
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