Use After Free in Apple macOS
CVE-2021-4128
When transitioning in and out of fullscreen mode, a graphics object was not correctly protected; resulting in memory corruption and a potentially exploitable crash.<br>*This bug only affects Firefox on MacOS. Other operating systems are unaffected.*. This vulnerability affects Firefox < 95.
Vulnerability class: Use-After-Free
Published · last modified .
CVSS v3 metric
CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H.
EPSS exploit prediction
EPSS: 0.006 (44.3th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 44th percentile — 44.3% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.005 · newest: 0.006 · change: +0.000
Affected products
- Apple macOS
- Mozilla Firefox — versions unspecified
Weakness classification (CWE)
References
- www.mozilla.org/security/advisories/mfsa2021-52/ (Vendor Advisory)
- bugzilla.mozilla.org/show_bug.cgi (Exploit, Patch, Issue Tracking, Vendor Advisory)
Frequently asked questions
- What is CVE-2021-4128?
- CVE-2021-4128 is a medium-severity vulnerability in Apple macOS, classified under Use After Free. CVSS score: 6.5/10. Published 2022-12-22.
- How severe is CVE-2021-4128?
- Medium severity. CVSS v3 base score is 6.5 out of 10.