Mozilla Foundation Security Advisory 2020-14

Security Vulnerabilities fixed in Thunderbird 68.7.0

Announced
April 9, 2020
Impact
critical
Products
Thunderbird
Fixed in
  • Thunderbird 68.7

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-2020-6819: Use-after-free while running the nsDocShell destructor

Reporter
Francisco Alonso @revskills working with Javier Marcos of @JMPSec
Impact
critical
Description

Under certain conditions, when running the nsDocShell destructor, a race condition can cause a use-after-free.

References

#CVE-2020-6820: Use-after-free when handling a ReadableStream

Reporter
Francisco Alonso @revskills working with Javier Marcos of @JMPSec
Impact
critical
Description

Under certain conditions, when handling a ReadableStream, a race condition can cause a use-after-free.

References

#CVE-2020-6821: Uninitialized memory could be read when using the WebGL copyTexSubImage method

Reporter
Jeff Gilbert, Kenneth Russell
Impact
high
Description

When reading from areas partially or fully outside the source resource with WebGL's copyTexSubImage method, the specification requires the returned values be zero. Previously, this memory was uninitialized, leading to potentially sensitive data disclosure.

References

#CVE-2020-6822: Out of bounds write in GMPDecodeData when processing large images

Reporter
Deian Stefan
Impact
moderate
Description

On 32-bit builds, an out of bounds write could have occurred when processing an image larger than 4 GB in GMPDecodeData. It is possible that with enough effort this could have been exploited to run arbitrary code.

References

#CVE-2020-6825: Memory safety bugs fixed in Thunderbird 68.7.0

Reporter
Mozilla developers
Impact
high
Description

Mozilla developers Tyson Smith and Christian Holler reported memory safety bugs present in Firefox 74 and Firefox ESR 68.6. 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