Coturn 4.10.0 contains an uninitialized memory disclosure vulnerability that allows remote unauthenticated attackers to leak stack memory contents by sending a TURN Allocate request without credentials. Attackers can exploit the stun_init_error_response_common_str() function in src/client/ns_turn_msg.c, which fails to zero-initialize the avalue buffer before computing its length with strlen() and copying leaked stack bytes into the ERROR-CODE reason phrase, exposing pointer fragments that weaken ASLR and enable precise version fingerprinting.
https://github.com/coturn/coturn/releases/tag/4.11.0
https://github.com/coturn/coturn/pull/1878
https://github.com/coturn/coturn/commit/741b2983cc52f967dd08c438fd72a5f08f13ca27
Published: 2026-10-07
Updated: 2026-10-07
Base Score: 5
Vector: CVSS2#AV:N/AC:L/Au:N/C:P/I:N/A:N
Severity: Medium
Base Score: 5.3
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
Severity: Medium
Base Score: 6.9
Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N
Severity: Medium
EPSS: 0.00311