Use After Free in Mozilla Firefox
CVE-2018-18500
A use-after-free vulnerability can occur while parsing an HTML5 stream in concert with custom HTML elements. This results in the stream parser object being freed while still in use, leading to a potentially exploitable crash. This vulnerab…
Vulnerability class: Use-After-Free
EPSS: 0.127 (95.8th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.
Affected products
- Mozilla Firefox
- Mozilla Firefox_esr
- Mozilla Thunderbird
- Canonical Ubuntu_linux — versions 14.04, 16.04, 18.04
- Debian Debian_linux — versions 8.0, 9.0
- Redhat Enterprise_linux_desktop — versions 6.0, 7.0
- Redhat Enterprise_linux_server — versions 6.0, 7.0
- Redhat Enterprise_linux_server_aus — versions 7.6
- Redhat Enterprise_linux_server_eus — versions 7.6
- Redhat Enterprise_linux_server_tus — versions 7.6
Weakness classification (CWE)
Public proof-of-concept exploits
References
- security@mozilla.org (x_refsource_REDHAT, vendor-advisory, Third Party Advisory)
- security@mozilla.org (x_refsource_CONFIRM, Vendor Advisory)
- security@mozilla.org (x_refsource_UBUNTU, vendor-advisory, Third Party Advisory)
- security@mozilla.org (VDB Entry, Third Party Advisory, vdb-entry, x_refsource_BID)
- security@mozilla.org (vendor-advisory, Third Party Advisory, x_refsource_GENTOO)
- security@mozilla.org (x_refsource_UBUNTU, vendor-advisory, Third Party Advisory)
- security@mozilla.org (x_refsource_REDHAT, vendor-advisory, Third Party Advisory)
- security@mozilla.org (x_refsource_REDHAT, vendor-advisory, Third Party Advisory)
- security@mozilla.org (x_refsource_CONFIRM, Vendor Advisory)
- security@mozilla.org (vendor-advisory, Third Party Advisory, x_refsource_DEBIAN)
Frequently asked questions
- What is CVE-2018-18500?
- CVE-2018-18500 is a critical-severity vulnerability in Mozilla Firefox, classified under Use After Free. CVSS score: 9.8/10. Published 2019-02-05.
- How severe is CVE-2018-18500?
- Critical severity. CVSS v3 base score is 9.8 out of 10.
- Is CVE-2018-18500 known to be exploited?
- 5 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.