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Mozilla Foundation Security Advisory 2023-55

Security Vulnerabilities fixed in Thunderbird 115.6

Announced
December 19, 2023
Impact
high
Products
Thunderbird
Fixed in
  • Thunderbird 115.6

#CVE-2023-50762: Truncated signed text was shown with a valid OpenPGP signature

Reporter
Marcus Brinkmann
Impact
high
Description

When processing a PGP/MIME payload that contains digitally signed text, the first paragraph of the text was never shown to the user. This is because the text was interpreted as a MIME message and the first paragraph was always treated as an email header section. A digitally signed text from a different context, such as a signed GIT commit, could be used to spoof an email message.

References

#CVE-2023-50761: S/MIME signature accepted despite mismatching message date

Reporter
Marcus Brinkmann
Impact
high
Description

The signature of a digitally signed S/MIME email message may optionally specify the signature creation date and time. If present, Thunderbird did not compare the signature creation date with the message date and time, and displayed a valid signature despite a date or time mismatch. This could be used to give recipients the impression that a message was sent at a different date or time.

References

#CVE-2023-6856: Heap-buffer-overflow affecting WebGL DrawElementsInstanced method with Mesa VM driver

Reporter
DoHyun Lee
Impact
high
Description

The WebGL DrawElementsInstanced method was susceptible to a heap buffer overflow when used on systems with the Mesa VM driver. This issue could allow an attacker to perform remote code execution and sandbox escape.

References

#CVE-2023-6857: Symlinks may resolve to smaller than expected buffers

Reporter
Jed Davis
Impact
moderate
Description

When resolving a symlink, a race may occur where the buffer passed to readlink may actually be smaller than necessary.
This bug only affects Thunderbird on Unix-based operating systems (Android, Linux, MacOS). Windows is unaffected.

References

#CVE-2023-6858: Heap buffer overflow in nsTextFragment

Reporter
Irvan Kurniawan
Impact
moderate
Description

Thunderbird was susceptible to a heap buffer overflow in nsTextFragment due to insufficient OOM handling.

References

#CVE-2023-6859: Use-after-free in PR_GetIdentitiesLayer

Reporter
Irvan Kurniawan
Impact
moderate
Description

A use-after-free condition affected TLS socket creation when under memory pressure.

References

#CVE-2023-6860: Potential sandbox escape due to VideoBridge lack of texture validation

Reporter
Andrew Osmond
Impact
moderate
Description

The VideoBridge allowed any content process to use textures produced by remote decoders. This could be abused to escape the sandbox.

References

#CVE-2023-6861: Heap buffer overflow affected nsWindow::PickerOpen(void) in headless mode

Reporter
Yangkang of 360 ATA Team
Impact
moderate
Description

The nsWindow::PickerOpen(void) method was susceptible to a heap buffer overflow when running in headless mode.

References

#CVE-2023-6862: Use-after-free in nsDNSService

Reporter
Randell Jesup
Impact
moderate
Description

A use-after-free was identified in the nsDNSService::Init. This issue appears to manifest rarely during start-up.

References

#CVE-2023-6863: Undefined behavior in ShutdownObserver()

Reporter
Ronald Crane
Impact
low
Description

The ShutdownObserver() was susceptible to potentially undefined behavior due to its reliance on a dynamic type that lacked a virtual destructor.

References

#CVE-2023-6864: Memory safety bugs fixed in Firefox 121, Firefox ESR 115.6, and Thunderbird 115.6

Reporter
Andrew McCreight, Karl Tomlinson, Valentin Gosu, Randell Jesup, Yury Delendik, and the Mozilla Fuzzing Team
Impact
high
Description

Memory safety bugs present in Firefox 120, Firefox ESR 115.5, and Thunderbird 115.5. 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