vulnerability
MFSA2021-07 Firefox: Security Vulnerabilities fixed in Firefox 86 (CVE-2021-23975)
| Severity | CVSS | Published | Added | Modified |
|---|---|---|---|---|
| 4 | (AV:N/AC:M/Au:N/C:N/I:P/A:N) | Feb 23, 2021 | Feb 24, 2021 | Mar 27, 2026 |
Severity
4
CVSS
(AV:N/AC:M/Au:N/C:N/I:P/A:N)
Published
Feb 23, 2021
Added
Feb 24, 2021
Modified
Mar 27, 2026
Description
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.
Solution
mozilla-firefox-upgrade-86_0
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