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Mozilla Foundation Security Advisory 2020-22

Security Vulnerabilities fixed in Thunderbird 68.9.0

Announced
June 2, 2020
Impact
high
Products
Thunderbird
Fixed in
  • Thunderbird 68.9

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-2020-12399: Timing attack on DSA signatures in NSS library

Reporter
Cesar Pereida Garcia and the Network and Information Security Group (NISEC) at Tampere University
Impact
high
Description

NSS has shown timing differences when performing DSA signatures, which was exploitable and could eventually leak private keys.

References

#CVE-2020-12405: Use-after-free in SharedWorkerService

Reporter
Marcin 'Icewall' Noga of Cisco Talos
Impact
high
Description

When browsing a malicious page, a race condition in our SharedWorkerService could occur and lead to a potentially exploitable crash.

References

#CVE-2020-12406: JavaScript Type confusion with NativeTypes

Reporter
Iain Ireland
Impact
high
Description

Mozilla developer Iain Ireland discovered a missing type check during unboxed objects removal, resulting in a crash. We presume that with enough effort that it could be exploited to run arbitrary code.

References

#CVE-2020-12410: Memory safety bugs fixed in Thunderbird 68.9.0

Reporter
Mozilla developers
Impact
high
Description

Mozilla developers Tom Tung and Karl Tomlinson reported memory safety bugs present in Firefox 68.8. 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

#CVE-2020-12398: Security downgrade with IMAP STARTTLS leads to information leakage

Reporter
Damian Poddebniak
Impact
high
Description

If Thunderbird is configured to use STARTTLS for an IMAP server, and the server sends a PREAUTH response, then Thunderbird will continue with an unencrypted connection, causing email data to be sent without protection.

References