Auth bypass in Mozilla Firefox

CVE-2021-23975

The developer page about:memory has a Measure function for exploring what object types the browser has allocated and their sizes. When this function was invoked we incorrectly called the sizeof function, instead of using the API method that checks for invalid pointers. This vulnerability affects Firefox < 86.

Vulnerability class: Broken Access Control

EPSS: 0.010 (59.8th percentile) — read the EPSS interpretation.

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:H/A:N.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2021-23975?
CVE-2021-23975 is a medium-severity vulnerability in Mozilla Firefox, classified under Missing Authorization. CVSS score: 6.5/10. Published 2021-02-26.
How severe is CVE-2021-23975?
Medium severity. CVSS v3 base score is 6.5 out of 10.