Permissions, Privileges, and Access Controls in Mozilla Firefox - CVE-2019-11738

Vulnerability identifier: #VU20832

CSH Severity: Low

CVSS v4: 6.3 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N]

CVE-ID: CVE-2019-11738

CWE-ID: CWE-264

Exploitation vector: Remote access

Exploit availability: No public exploit available

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.

Mozilla Firefox
Firefox ESR
Arch Linux
Red Hat Enterprise Linux for x86_64
firefox (Ubuntu package)

Install updates from vendor's website.

Mozilla Firefox - update to 69.0
firefox (Ubuntu package) - addressed in versions 69.0+build2-0ubuntu0.16.04.4, 69.0+build2-0ubuntu0.18.04.1, 69.0+build2-0ubuntu0.19.04.1, 69.0.2+build1-0ubuntu0.16.04.1, 69.0.2+build1-0ubuntu0.18.04.1, 69.0.2+build1-0ubuntu0.19.04.1
Firefox ESR - update to 68.1.0

• https://www.mozilla.org/en-US/security/advisories/mfsa2019-25/

• Multiple vulnerabilities in Mozilla Firefox
• Multiple vulnerabilities in Mozilla Firefox ESR
• Arch Linux update for firefox
• Ubuntu update for Firefox
• Red Hat update for firefox
• Ubuntu regressions update for Firefox