CVE-2026-108538A security vulnerability has been detected in GPAC up to 26.07.0. The impacted element is the function gf_mx_v of the file utils/os_thread.c of the component MP4Box. Such manipulation leads to use after free. The attack can be launched remotely. The exploit has been disclosed publicly and may be used. The vendor was contacted early about this disclosure but did not respond in any way.