Vulnerability identifier: #VU18041

Vulnerability risk: Medium

CVSSv3.1: 5.3 [CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N/E:U/RL:O/RC:C]

CVE-ID: CVE-2019-9803

CWE-ID: CWE-264

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 perform man-in-the-middle attack.

The vulnerability exists due to incorrect enforcement of Upgrade-Insecure-Requests (UIR) for same-origin navigation allowing the browser to navigate to HTTP URL instead of HTTPS. A remote attacker can perform man-in-the-middle (MitM) attack and gain access to sensitive information.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Mozilla Firefox: 61.0 - 65.0.2

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External links
http://www.mozilla.org/en-US/security/advisories/mfsa2019-07/
http://bugzilla.mozilla.org/show_bug.cgi?id=1515863
http://bugzilla.mozilla.org/show_bug.cgi?id=1437009

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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.