CVE-2025-4083Critical· 9.1▾ MidnightA process isolation vulnerability in Thunderbird stemmed from improper handling of javascript: URIs, which could allow content to execute in the top-level document's process instead of the intended frame, potentially enabling a sandbox e…
▾ Midnight zone — Critical, or high with PoC / in-the-wild
impact 50.1 · likelihood 0.1 · exploitation 0
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Exploit-prediction probability, daily snapshots since Sep 30.
Disclosure to exploitation, from the record and what we observed since indexing it.
Disclosed via NVD
0.5%
Last analysed / modified upstream
A process isolation vulnerability in Thunderbird stemmed from improper handling of javascript: URIs, which could allow content to execute in the top-level document's process instead of the intended frame, potentially enabling a sandbox escape. This vulnerability was fixed in Firefox 138, Firefox ESR 128.10, Firefox ESR 115.23, Thunderbird 138, and Thunderbird 128.10.
firefox < 115.23firefox < 138.0firefox >= 128.0, < 128.10thunderbird < 128.10.0thunderbird < 138.0Upgrade past the affected range:
firefox 128.10thunderbird 138.0Connected by shared product, vendor, weakness, or advisory.
CVE-2025-2817High· 8.8Thunderbird's update mechanism allowed a medium-integrity user process to interfere with the SYSTEM-level updater by manipulating the file-locking behavior
CVE-2026-118008High· 8.8Privilege escalation in the DOM: Navigation component
CVE-2026-117999NoneRace condition in the IPC component
CVE-2026-117976NoneSite isolation issue in the DOM: Navigation component
CVE-2026-118027NoneFrame poisoning in the Layout component
CVE-2026-118024NoneUse-after-free in the Graphics: Text component