Mozilla Foundation Security Advisory 2026-44

Security Vulnerabilities fixed in Thunderbird 140.10.2

Announced
May 8, 2026
Impact
high
Products
Thunderbird
Fixed in
  • Thunderbird 140.10.2

In general, these flaws cannot be exploited through email in the Thunderbird product because scripting is disabled when reading mail, but are potentially risks in browser or browser-like contexts.

#CVE-2026-8090: Use-after-free in the DOM: Networking component

Reporter
Kevin Brosnan
Impact
high
References

#CVE-2026-8094: Other issue in the WebRTC component

Reporter
Michael Froman
Impact
high
References

#CVE-2026-8092: Memory safety bugs fixed in Thunderbird ESR 140.10.2 and Thunderbird 150.0.2

Reporter
Andrew McCreight, Christian Holler, Lee Salzman, Maurice Dauer, Tom Schuster, Wayne Mery and the Mozilla Fuzzing Team
Impact
high
Description

Memory safety bugs present in Thunderbird ESR 140.10.1 and Thunderbird 150.0.1. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code.

References