Privilege escalation in Mozilla Firefox

CVE-2021-23999

If a Blob URL was loaded through some unusual user interaction, it could have been loaded by the System Principal and granted additional privileges that should not be granted to web content. This vulnerability affects Firefox ESR < 78.10…

Vulnerability class: Privilege Escalation

EPSS: 0.013 (66.8th percentile) — read the EPSS interpretation.

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.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2021-23999?
CVE-2021-23999 is a high-severity vulnerability in Mozilla Firefox, classified under Improper Privilege Management. CVSS score: 8.8/10. Published 2021-06-24.
How severe is CVE-2021-23999?
High severity. CVSS v3 base score is 8.8 out of 10.