On Windows, a compromised content process could use bad StreamData sent over AudioIPC to trigger a use-after-free in the Browser process. This could have led to a sandbox escape. This vulnerability affects Firefox < 136, Firefox ESR < 115.21, Firefox ESR < 128.8, Thunderbird < 136, and Thunderbird < 128.8.
https://www.mozilla.org/security/advisories/mfsa2025-18/
https://www.mozilla.org/security/advisories/mfsa2025-17/
https://www.mozilla.org/security/advisories/mfsa2025-16/
https://www.mozilla.org/security/advisories/mfsa2025-15/