#VU7063 Use-after-free error in Firefox ESR - CVE-2017-5472

Vulnerability identifier: #VU7063

Vulnerability risk: High

CVSSv4.0: 8.1 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Amber]

CVE-ID: CVE-2017-5472

CWE-ID: CWE-416

Exploitation vector: Network

Exploit availability: No

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

Vendor: Mozilla

Description
The vulnerability allows a remote attacker to execute arbitrary code on the target system.

The weakness exists due to use-after-free error with the frameloader during tree reconstruction while regenerating CSS layout. A remote attacker can use a node in the tree that no longer exists, trigger memory corruption and execute arbitrary code with privileges of the current user.

Successful exploitation of the vulnerability may result in system compromise.

Mitigation
Update to version 52.2.

Vulnerable software versions

Firefox ESR: 38.0 - 38.8.0, 45.0 - 45.8, 52.0.1

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External links
https://www.mozilla.org/en-US/security/advisories/mfsa2017-16/

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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.