This vulnerability is a use‑after‑free in the DOM core and HTML component of Mozilla Firefox. An attacker could exploit the ability to access memory that has already been freed, potentially leading to arbitrary code execution, memory corruption, or a denial‑of‑service crash. The weakness is a classic instance of improper memory management.

Affected systems are Mozilla Firefox and its Extended Support Release channels. Versions earlier than Firefox 158, ESR 115.43, and ESR 153.5 are vulnerable. All users of those releases should consider the upgrade path.

No official CVSS or EPSS scores are published, and the vulnerability is not present in the CISA KEV catalog, so the exact exploitation probability is unknown. Based on the nature of DOM vulnerabilities, the likely attack vector is a malicious web page accessed by the user. The lack of a public exploit does not eliminate the risk, and patching remains the most reliable defense.