#VU6313 Use-after-free in Mozilla Firefox and Firefox ESR - CVE-2017-5433

Vulnerability identifier: #VU6313

Vulnerability risk: High

CVSSv4.0: 6.1 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Amber]

CVE-ID: CVE-2017-5433

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 execute arbitrary code on the target system.

The vulnerability exists due to use-after-free error in SMIL animation functions, when pointers to animation elements in an array are dropped from the animation controller while still in use. A remote attacker can trigger memory corruption and execute arbitrary code on the target system.

Successful exploitation of the vulnerability may allow an attacker to compromise vulnerable system.

Mitigation
Update to Firefox 53, Firefox ESR 45.9 or Firefox ESR 52.1.

Vulnerable software versions

Mozilla Firefox: 52 - 52.0.2

Firefox ESR: 45 - 45.8, 52.0 - 52.0.2

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External links
https://www.mozilla.org/en-US/security/advisories/mfsa2017-10/
https://www.mozilla.org/en-US/security/advisories/mfsa2017-11/
https://www.mozilla.org/en-US/security/advisories/mfsa2017-12/

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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.