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Mozilla Foundation Security Advisory 2023-56

Security Vulnerabilities fixed in Firefox 121

Announced
December 19, 2023
Impact
high
Products
Firefox
Fixed in
  • Firefox 121

#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-2023-6135: NSS susceptible to "Minerva" attack

Reporter
George Pantela (Red Hat) and Hubert Kario (Red Hat)
Impact
high
Description

Multiple NSS NIST curves were susceptible to a side-channel attack known as "Minerva". This attack could potentially allow an attacker to recover the private key.

References

#CVE-2023-6865: Potential exposure of uninitialized data in EncryptingOutputStream

Reporter
Jan Varga
Impact
high
Description

EncryptingOutputStream was susceptible to exposing uninitialized data. This issue could only be abused in order to write data to a local disk which may have implications for private browsing mode.

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 Firefox 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

Firefox 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-2023-6866: TypedArrays lack sufficient exception handling

Reporter
Tom Schuster
Impact
moderate
Description

TypedArrays can be fallible and lacked proper exception handling. This could lead to abuse in other APIs which expect TypedArrays to always succeed.

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-2023-6867: Clickjacking permission prompts using the popup transition

Reporter
Hafiizh
Impact
moderate
Description

The timing of a button click causing a popup to disappear was approximately the same length as the anti-clickjacking delay on permission prompts. It was possible to use this fact to surprise users by luring them to click where the permission grant button would be about to appear.

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-2023-6868: WebPush requests on Firefox for Android did not require VAPID key

Reporter
John-Mark Gurney
Impact
moderate
Description

In some instances, the user-agent would allow push requests which lacked a valid VAPID even though the push manager subscription defined one. This could allow empty messages to be sent from unauthorized parties.
This bug only affects Firefox on Android.

References

#CVE-2023-6869: Content can paint outside of sandboxed iframe

Reporter
Oriol Brufau
Impact
low
Description

A <dialog> element could have been manipulated to paint content outside of a sandboxed iframe. This could allow untrusted content to display under the guise of trusted content.

References

#CVE-2023-6870: Android Toast notifications may obscure fullscreen event notifications

Reporter
Hafiizh
Impact
low
Description

Applications which spawn a Toast notification in a background thread may have obscured fullscreen notifications displayed by Firefox.
This issue only affects Android versions of Firefox and Firefox Focus.

References

#CVE-2023-6871: Lack of protocol handler warning in some instances

Reporter
Edward "JankhJankh" Prior
Impact
low
Description

Under certain conditions, Firefox did not display a warning when a user attempted to navigate to a new protocol handler.

References

#CVE-2023-6872: Browsing history leaked to syslogs via GNOME

Reporter
honorton via Tor Browser
Impact
low
Description

Browser tab titles were being leaked by GNOME to system logs. This could potentially expose the browsing habits of users running in a private tab.

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, Randell Jesup, Valentin Gosu, Karl Tomlinson, 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

#CVE-2023-6873: Memory safety bugs fixed in Firefox 121

Reporter
Andrew McCreight, Yury Delendik
Impact
high
Description

Memory safety bugs present in Firefox 120. 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