#VU6327 Out-of-bounds write in Mozilla Firefox and Firefox ESR - CVE-2017-5443

Vulnerability identifier: #VU6327

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-2017-5443

CWE-ID: CWE-787

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 boundary error while decoding improperly formed BinHex format archives. A remote attacker can trigger out-of-bounds write 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.