Information disclosure in Mozilla Firefox and Firefox ESR - CVE-2021-43542
Published: December 7, 2021
Vulnerability identifier: #VU58612
CSH Severity: Low
CVSS v4.0: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear
CVE-ID: CVE-2021-43542
CWE-ID: CWE-200
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vendor: Mozilla
Affected software:
Mozilla Firefox
Firefox ESR
Mozilla Firefox
Firefox ESR
Detailed vulnerability description
The vulnerability allows a remote attacker to gain access to potentially sensitive information.
The vulnerability exists due to the way Firefox handles XMLHttpRequest requests. A remote attacker can initiate a XMLHttpRequest and identify installed applications by probing error messages for loading external protocols.
How to mitigate CVE-2021-43542
Install updates from vendor's website.