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Mozilla Foundation Security Advisory 2020-26

Security Vulnerabilities fixed in Thunderbird 68.10.0

Announced
June 30, 2020
Impact
high
Products
Thunderbird
Fixed in
  • Thunderbird 68.10

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-2020-12417: Memory corruption due to missing sign-extension for ValueTags on ARM64

Reporter
Deian Stefan
Impact
high
Description

Due to confusion about ValueTags on JavaScript Objects, an object may pass through the type barrier, resulting in memory corruption and a potentially exploitable crash.
Note: this issue only affects Firefox on ARM64 platforms.

References

#CVE-2020-12418: Information disclosure due to manipulated URL object

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

Manipulating individual parts of a URL object could have caused an out-of-bounds read, leaking process memory to malicious JavaScript.

References

#CVE-2020-12419: Use-after-free in nsGlobalWindowInner

Reporter
worcester12345
Impact
high
Description

When processing callbacks that occurred during window flushing in the parent process, the associated window may die; causing a use-after-free condition. This could have led to memory corruption and a potentially exploitable crash.

References

#CVE-2020-12420: Use-After-Free when trying to connect to a STUN server

Reporter
Byron Campen
Impact
high
Description

When trying to connect to a STUN server, a race condition could have caused a use-after-free of a pointer, leading to memory corruption and a potentially exploitable crash.

References

#CVE-2020-15646: Automatic account setup leaks Microsoft Exchange login credentials

Reporter
Magnus Melin
Impact
high
Description

If an attacker intercepts Thunderbird's initial attempt to perform automatic account setup using the Microsoft Exchange autodiscovery mechanism, and the attacker sends a crafted response, then Thunderbird sends username and password over https to a server controlled by the attacker.

References

#CVE-2020-12421: Add-On updates did not respect the same certificate trust rules as software updates

Reporter
Chuck Harmston, Robert Hardy
Impact
moderate
Description

When performing add-on updates, certificate chains terminating in non-built-in-roots were rejected (even if they were legitimately added by an administrator.) This could have caused add-ons to become out-of-date silently without notification to the user.

References