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Mozilla Foundation Security Advisory 2023-46

Security Vulnerabilities fixed in Firefox ESR 115.4

Announced
October 24, 2023
Impact
high
Products
Firefox ESR
Fixed in
  • Firefox ESR 115.4

#CVE-2023-5721: Queued up rendering could have allowed websites to clickjack

Reporter
Kelsey Gilbert
Impact
high
Description

It was possible for certain browser prompts and dialogs to be activated or dismissed unintentionally by the user due to an insufficient activation-delay.

References

#CVE-2023-5732: Address bar spoofing via bidirectional characters

Reporter
Armin Ebert
Impact
moderate
Description

An attacker could have created a malicious link using bidirectional characters to spoof the location in the address bar when visited.

References

#CVE-2023-5724: Large WebGL draw could have led to a crash

Reporter
pwn2car
Impact
moderate
Description

Drivers are not always robust to extremely large draw calls and in some cases this scenario could have led to a crash.

References

#CVE-2023-5725: WebExtensions could open arbitrary URLs

Reporter
Shaheen Fazim
Impact
moderate
Description

A malicious installed WebExtension could open arbitrary URLs, which under the right circumstance could be leveraged to collect sensitive user data.

References

#CVE-2023-5726: Full screen notification obscured by file open dialog on macOS

Reporter
Edgar Chen and Hafiizh
Impact
moderate
Description

A website could have obscured the full screen notification by using the file open dialog. This could have led to user confusion and possible spoofing attacks.
Note: This issue only affected macOS operating systems. Other operating systems are unaffected.

References

#CVE-2023-5727: Download Protections were bypassed by .msix, .msixbundle, .appx, and .appxbundle files on Windows

Reporter
Marco Bonardo
Impact
moderate
Description

The executable file warning was not presented when downloading .msix, .msixbundle, .appx, and .appxbundle files, which can run commands on a user's computer.
Note: This issue only affected Windows operating systems. Other operating systems are unaffected.

References

#CVE-2023-5728: Improper object tracking during GC in the JavaScript engine could have led to a crash.

Reporter
anbu
Impact
moderate
Description

During garbage collection extra operations were performed on a object that should not be. This could have led to a potentially exploitable crash.

References

#CVE-2023-5730: Memory safety bugs fixed in Firefox 119, Firefox ESR 115.4, and Thunderbird 115.4.1

Reporter
Randell Jesup, Andrew McCreight, Jed Davis, and the Mozilla Fuzzing Team
Impact
high
Description

Memory safety bugs present in Firefox 118, Firefox ESR 115.3, and Thunderbird 115.3. 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