A compromised child process can trigger a use‑after‑free in Firefox’s GPU or browser process through WebGPU IPC calls, allowing the attacker to potentially escape the child process sandbox. The flaw stems from improper deallocation of GPU resource handles (CWE‑416) and can lead to execution of arbitrary code or data disclosure within the host process.

All Firefox installations starting with version 142 up to 144.0.1 on any platform are affected. The vulnerability was resolved in Firefox 144.0.2 and later releases.

The CVSS score of 9.8 indicates critical severity, but the EPSS score of less than 1% suggests a very low likelihood of active exploitation. The vulnerability is not listed in CISA’s KEV catalog. Exploitability requires a child process to be compromised and to send malicious WebGPU IPC messages; no public exploitation reports exist yet, so the primary threat is theoretical until an adversary finds a vector to compromise a child process.