Vulnerability in Mozilla Firefox
CVE-2021-23997
Due to unexpected data type conversions, a use-after-free could have occurred when interacting with the font cache. We presume that with enough effort this could have been exploited to run arbitrary code. This vulnerability affects Firefox < 88.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 8.8 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H.
EPSS exploit prediction
EPSS: 0.008 (56.3th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 56th percentile — 56.3% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.008 · newest: 0.008 · change: 0.000
Affected products
- Mozilla Firefox — versions unspecified
Weakness classification (CWE)
References
- www.mozilla.org/security/advisories/mfsa2021-16/ (Release Notes, Vendor Advisory)
- bugzilla.mozilla.org/show_bug.cgi (Permissions Required, Issue Tracking, Vendor Advisory)
Frequently asked questions
- What is CVE-2021-23997?
- CVE-2021-23997 is a high-severity vulnerability in Mozilla Firefox, classified under Incorrect Conversion between Numeric Types. CVSS score: 8.8/10. Published 2021-06-24.
- How severe is CVE-2021-23997?
- High severity. CVSS v3 base score is 8.8 out of 10.