vulnerability
Oracle Linux: CVE-2021-23987: ELSA-2021-0990: firefox security update (IMPORTANT) (Multiple Advisories)
| Severity | CVSS | Published | Added | Modified |
|---|---|---|---|---|
| 7 | (AV:N/AC:M/Au:N/C:P/I:P/A:P) | Mar 23, 2021 | Mar 26, 2021 | Dec 3, 2025 |
Severity
7
CVSS
(AV:N/AC:M/Au:N/C:P/I:P/A:P)
Published
Mar 23, 2021
Added
Mar 26, 2021
Modified
Dec 3, 2025
Description
Mozilla developers and community members reported memory safety bugs present in Firefox 86 and Firefox ESR 78.8. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code. This vulnerability affects Firefox ESR < 78.9, Firefox < 87, and Thunderbird < 78.9.
The Mozilla Foundation Security Advisory describes this issue as:
Mozilla developers and community members reported memory safety bugs present in Firefox 86 and Firefox ESR 78.8. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code.
The Mozilla Foundation Security Advisory describes this issue as:
Mozilla developers and community members reported memory safety bugs present in Firefox 86 and Firefox ESR 78.8. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code.
Solutions
oracle-linux-upgrade-firefoxoracle-linux-upgrade-thunderbird
Rapid7 Labs
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