CVE-2026-12300
published 2026-06-16CVE-2026-12300: Memory safety bug fixed in Thunderbird 152. This vulnerability was fixed in Firefox 152 and Thunderbird 152.
PriorityP425medium5.3CVSS 3.1
AVNACLPRNUINSUCLINAN
EPSS
0.25%
16.5th percentile
Memory safety bug fixed in Thunderbird 152. This vulnerability was fixed in Firefox 152 and Thunderbird 152.
Affected
2 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| mozilla | firefox | < Firefox 152 | Firefox 152 |
| mozilla | thunderbird | < Thunderbird 152 | Thunderbird 152 |
CVSS provenance
nvdv3.15.3MEDIUMCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
vendor_redhat5.3MEDIUM
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Red Hat
firefox: thunderbird: Memory safety bug fixed in Firefox 152
vendor_redhat·2026-06-16·CVSS 5.3
CVE-2026-12300 [MEDIUM] CWE-787 firefox: thunderbird: Memory safety bug fixed in Firefox 152
firefox: thunderbird: Memory safety bug fixed in Firefox 152
Memory safety bug fixed in Firefox 152. This vulnerability was fixed in Firefox 152 and Thunderbird 152.
A flaw was found in Firefox and Thunderbird. The Mozilla Foundation's Security Advisory describes the following issue:
Memory safety bug fixed in Thunderbird 152
Statement: Red Hat Product Security rates the severity of this flaw as determined by the Mozilla Foundation Security Advisory.
Package: firefox (Red Hat Enterprise Linux 10) - Not affected
Package: rhel10/firefox-flatpak (Red Hat Enterprise Linux 10) - Not affected
Package: rhel10/thunderbird-flatpak (Red Hat Enterprise Linux 10) - Not affected
Package: thunderbird (Red Hat Enterprise Linux 10) - Not affected
Package: firefox (Red Hat Enterprise Linux 6) - Not
Mozilla
Mozilla Foundation Security Advisory 2026-60: CVE-2026-12300
vendor_mozilla·CVSS 5.3
CVE-2026-12300 [MEDIUM] Mozilla Foundation Security Advisory 2026-60: CVE-2026-12300
Mozilla Foundation Security Advisory 2026-60
CVE: CVE-2026-12300
Product: Thunderbird
Impact: high
Fixed in: Thunderbird 152
Mozilla
Mozilla Foundation Security Advisory 2026-57: CVE-2026-12300
vendor_mozilla·CVSS 5.3
CVE-2026-12300 [MEDIUM] Mozilla Foundation Security Advisory 2026-57: CVE-2026-12300
Mozilla Foundation Security Advisory 2026-57
CVE: CVE-2026-12300
Product: Firefox
Impact: high
Fixed in: Firefox 152
GHSA
Memory safety bug fixed in Firefox 152.
ghsa_unreviewed·2026-06-16
CVE-2026-12300 [MEDIUM] CWE-119 Memory safety bug fixed in Firefox 152.
Memory safety bug fixed in Firefox 152. This vulnerability was fixed in Firefox 152.
No detection rules found.
No public exploits indexed.
2026-06-16
Published