#VU52334 Use-fater-free


Published: 2021-04-19

Vulnerability identifier: #VU52334

Vulnerability risk: High

CVSSv3.1: 7.7 [CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2021-23995

CWE-ID: CWE-416

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Mozilla Firefox
Client/Desktop applications / Web browsers
Firefox ESR
Client/Desktop applications / Web browsers

Vendor: Mozilla

Description

The vulnerability allows a remote attacker to compromise vulnerable system.

The vulnerability exists due to a boundary error when processing untrusted input, when Responsive Design Mode is enabled. A remote attacker can create a specially crafted web page, trick the victim into opening it using the affected software, trigger a use-after-fee error and execute arbitrary code on the target system.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Mozilla Firefox: 8.0.1 - 87.0

Firefox ESR: 78.0 - 78.9.0, 68.0 - 68.12.0, 60.0 - 60.9.0


CPE

External links
http://www.mozilla.org/en-US/security/advisories/mfsa2021-16/
http://www.mozilla.org/en-US/security/advisories/mfsa2021-15/


Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.


Latest bulletins with this vulnerability