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Mozilla Foundation Security Advisory 2021-42

Security Vulnerabilities fixed in Thunderbird 78.14

Announced
September 7, 2021
Impact
moderate
Products
Thunderbird
Fixed in
  • Thunderbird 78.14

#CVE-2021-38492: Navigating to "mk:" URL scheme could load Internet Explorer

Reporter
James Lee
Impact
moderate
Description

When delegating navigations to the operating system, Thunderbird would accept the mk scheme which might allow attackers to launch pages and execute scripts in Internet Explorer in unprivileged mode.
This bug only affects Thunderbird for Windows. Other operating systems are unaffected.

References

#CVE-2021-38493: Memory safety bugs fixed in Thunderbird 78.14 and Thunderbird 91.1

Reporter
Mozilla developers and community
Impact
high
Description

Mozilla developers Tyson Smith and Gabriele Svelto reported memory safety bugs present in Thunderbird 78.13. 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