#VU7844 Man-in-the-middle attack in Mozilla Firefox - CVE-2017-7781

Vulnerability identifier: #VU7844

Vulnerability risk: Low

CVSSv4.0: 4.5 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:A/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2017-7781

CWE-ID: CWE-20

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 conduct man-in-the-middle attack.

The weakness exists due to an elliptic curve point addition error when using mixed Jacobian-affine coordinates. A remote attacker can trick the victim into visiting a specially crafted website and use man-in-the-middle techniques to interfere with a connection and compute an incorrect shared secret.

Mitigation
Update to version 55.0.

Vulnerable software versions

Mozilla Firefox: 45.0 - 54.0

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External links
https://www.mozilla.org/en-US/security/advisories/mfsa2017-18/

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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.