Memory corruption in Mozilla Firefox - CVE-2019-9792

Vulnerability identifier: #VU18031

CSH Severity: High

CVSS v4: 8.6 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N]

CVE-ID: CVE-2019-9792

CWE-ID: CWE-119

Exploitation vector: Remote access

Exploit availability: Public exploit is available

The vulnerability allows a remote attacker to compromise vulnerable system.

The vulnerability exists due to a boundary error within the IonMonkey just-in-time (JIT) compiler that leaks an internal JS_OPTIMIZED_OUT magic value to the running script during a bailout. A remote attacker can trick the victim to visit a specially crafted web page, trigger memory corruption and execute arbitrary code on the system with privileges of the current user.

Successful exploitation of the vulnerability may allow an attacker to compromise vulnerable system.

Mozilla Firefox
Firefox ESR
Arch Linux
Red Hat Enterprise Linux for Scientific Computing
Red Hat Enterprise Linux for IBM z Systems
Red Hat Enterprise Linux Desktop
Red Hat Enterprise Linux Workstation
Red Hat Enterprise Linux Server
Red Hat Enterprise Linux for x86_64
Red Hat Enterprise Linux for Power
Opensuse
SUSE Package Hub for SUSE Linux Enterprise
firefox (Ubuntu package)
thunderbird (Ubuntu package)
firefox-esr (Debian package)
thunderbird (Debian package)
firefox-esr (Alpine package)
Mozilla Thunderbird

Install updates from vendor's website.

Mozilla Firefox - update to 66.0
firefox (Ubuntu package) - addressed in versions 66.0.1+build1-0ubuntu0.14.04.1, 66.0.2+build1-0ubuntu0.14.04.1, 66.0.2+build1-0ubuntu0.16.04.1, 66.0.2+build1-0ubuntu0.18.04.1, 66.0.2+build1-0ubuntu0.18.10.1, 66.0.3+build1-0ubuntu0.14.04.1, 66.0.3+build1-0ubuntu0.16.04.1, 66.0.3+build1-0ubuntu0.18.04.1, 66.0.3+build1-0ubuntu0.18.10.1
thunderbird (Ubuntu package) - addressed in versions 1:60.6.1+build2-0ubuntu0.14.04.1, 1:60.6.1+build2-0ubuntu0.16.04.1, 1:60.6.1+build2-0ubuntu0.18.04.1, 1:60.6.1+build2-0ubuntu0.18.10.1
Firefox ESR - update to 60.6.0
Mozilla Thunderbird - update to 60.6.0
firefox-esr (Debian package) - update to 60.6.0esr-1~deb9u1
thunderbird (Debian package) - update to 1:60.6.1-1~deb9u1
firefox-esr (Alpine package) - update to 60.6.1-r0

• Exploit #6130 - Spidermonkey - IonMonkey Leaks JS_OPTIMIZED_OUT Magic Value to Script (June 17, 2021)

• https://www.mozilla.org/en-US/security/advisories/mfsa2019-07/
• https://bugzilla.mozilla.org/show_bug.cgi?id=1532599

• Multiple vulnerabilities in Mozilla Firefox
• Multiple vulnerabilities in Mozilla Firefox ESR
• Debian update for firefox-esr
• Multiple vulnerabilities in Mozilla Thunderbird
• Ubuntu update for Firefox
• Ubuntu update for Thunderbird
• Ubuntu regression update for Firefox
• Debian update for thunderbird
• Ubuntu regression update for Firefox
• Arch Linux update for firefox
• OpenSUSE Linux update for MozillaThunderbird
• OpenSUSE Linux update for MozillaFirefox
• OpenSUSE Linux update for MozillaFirefox
• OpenSUSE Linux update for MozillaThunderbird
• Red Hat update for thunderbird
• Red Hat update for thunderbird
• Red Hat update for firefox
• Red Hat update for firefox
• Red Hat update for thunderbird
• Red Hat update for firefox
• Memory corruption in firefox-esr (Alpine package)