Use After Free in Mozilla Firefox
CVE-2019-9796
A use-after-free vulnerability can occur when the SMIL animation controller incorrectly registers with the refresh driver twice when only a single registration is expected. When a registration is later freed with the removal of the animation controller element, the refresh driver incorrectly leaves a dangling pointer to the driver's observer array. This vulnerability affects Thunderbird < 60.6, Firefox ESR < 60.6, and Firefox < 66.
Vulnerability class: Use-After-Free
EPSS: 0.020 (79.2th 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 — versions unspecified
- Mozilla Firefox Esr — versions unspecified
- Mozilla Thunderbird — versions unspecified
Weakness classification (CWE)
Public proof-of-concept exploits
References
- security@mozilla.org (x_refsource_MISC, Vendor Advisory)
- security@mozilla.org (x_refsource_MISC, Vendor Advisory)
- security@mozilla.org (x_refsource_MISC, Vendor Advisory)
- security@mozilla.org (Permissions Required, x_refsource_MISC, Issue Tracking, Vendor Advisory)
- security@mozilla.org (x_refsource_REDHAT, vendor-advisory, Third Party Advisory)
- security@mozilla.org (x_refsource_REDHAT, vendor-advisory, Third Party Advisory)
Frequently asked questions
- What is CVE-2019-9796?
- CVE-2019-9796 is a critical-severity vulnerability in Mozilla Firefox, classified under Use After Free. CVSS score: 9.8/10. Published 2019-04-26.
- How severe is CVE-2019-9796?
- Critical severity. CVSS v3 base score is 9.8 out of 10.
- Is CVE-2019-9796 known to be exploited?
- 1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.