vulnerability
MFSA2025-07 Firefox: Security Vulnerabilities fixed in Firefox 135 (CVE-2025-1020)
| Severity | CVSS | Published | Added | Modified |
|---|---|---|---|---|
| 10 | (AV:N/AC:L/Au:N/C:C/I:C/A:C) | Feb 4, 2025 | Feb 5, 2025 | Apr 15, 2026 |
Severity
10
CVSS
(AV:N/AC:L/Au:N/C:C/I:C/A:C)
Published
Feb 4, 2025
Added
Feb 5, 2025
Modified
Apr 15, 2026
Description
Memory safety bugs present in Firefox 134 and Thunderbird 134. 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 was fixed in Firefox 135 and Thunderbird 135.
Solution
mozilla-firefox-upgrade-135_0
Rapid7 Labs
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