Vulnerability identifier: #VU20832

Vulnerability risk: Low

CVSSv3.1: 3.2 [CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N/E:U/RL:O/RC:C]

CVE-ID: CVE-2019-11738

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 bypass CSP.

The vulnerability exists due to incorrect processing of Content Security Policy (CSP) directive if a hash-based source takes the empty string as input, that leads to execution of any javascript: URIs.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Mozilla Firefox: 66.0.2 - 68.0.2

---

External links
http://www.mozilla.org/en-US/security/advisories/mfsa2019-25/

---

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.