Vulnerability identifier: #VU5921

Vulnerability risk: High

CVSSv3.1: 8.3 [CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2017-5400

CWE-ID: CWE-265

Exploitation vector: Network

Exploit availability: No

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

Vendor: Mozilla

Description

The vulnerability allows a remote attacker to bypass implemented security mechanisms.

The vulnerability exists due to an error within asm.js. A remote attacker can perform a JIT-spray technique combined with a heap spray and bypass implemented ASLR and DEP protections.

Successful exploitation of the vulnerability may allow an attacker to leverage exploitation of other remote code execution vulnerabilities.

Mitigation
Update to Firefox 52.

Vulnerable software versions

Mozilla Firefox: 50.0 - 51.0.3

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External links
http://www.mozilla.org/en-US/security/advisories/mfsa2017-05/

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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.