CVE-2026-12308
published 2026-06-16CVE-2026-12308: Memory safety bug fixed in Thunderbird 152. This vulnerability was fixed in Firefox 152, Firefox ESR 140.12, Thunderbird 152, and Thunderbird 140.12.
PriorityP427medium5.3CVSS 3.1
AVNACLPRNUINSUCLINAN
EPSS
0.26%
17.7th percentile
Memory safety bug fixed in Thunderbird 152. This vulnerability was fixed in Firefox 152, Firefox ESR 140.12, Thunderbird 152, and Thunderbird 140.12.
Affected
8 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| mozilla | firefox | < Firefox 152 | Firefox 152 |
| mozilla | firefox | — | — |
| mozilla | firefox_esr | < Firefox ESR 140.12 | Firefox ESR 140.12 |
| mozilla | thunderbird | < Thunderbird 140.12 | Thunderbird 140.12 |
| mozilla | thunderbird | < Thunderbird 152 | Thunderbird 152 |
| mozilla | thunderbird | — | — |
| rhel10 | firefox-flatpak | — | — |
| rhel10 | thunderbird-flatpak | — | — |
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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VulDB
Mozilla Firefox up to 151 memory corruption (Nessus ID 321490)
vuldb·2026-06-19·CVSS 5.3
CVE-2026-12308 [MEDIUM] Mozilla Firefox up to 151 memory corruption (Nessus ID 321490)
A vulnerability classified as critical was found in Mozilla Firefox up to 151. This vulnerability affects unknown code. Executing a manipulation can lead to memory corruption.
This vulnerability appears as CVE-2026-12308. The attack may be performed from remote. There is no available exploit.
Upgrading the affected component is advised.
GHSA
Memory safety bug fixed in Firefox 152.
ghsa_unreviewed·2026-06-16
CVE-2026-12308 [MEDIUM] CWE-119 Memory safety bug fixed in Firefox 152.
Memory safety bug fixed in Firefox 152. This vulnerability was fixed in Firefox 152 and Firefox ESR 140.12.
Red Hat
firefox: thunderbird: Memory safety bug fixed in Thunderbird ESR 140.12
vendor_redhat·2026-06-16·CVSS 5.3
CVE-2026-12308 [MEDIUM] firefox: thunderbird: Memory safety bug fixed in Thunderbird ESR 140.12
firefox: thunderbird: Memory safety bug fixed in Thunderbird ESR 140.12
Memory safety bug fixed in Firefox 152. This vulnerability was fixed in Firefox 152, Firefox ESR 140.12, Thunderbird 152, and Thunderbird 140.12.
A flaw was found in Firefox and Thunderbird. The Mozilla Foundation's Security Advisory describes the following issue:
Memory safety bug fixed in Thunderbird ESR 140.12
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) - Affected
Package: rhel10/firefox-flatpak (Red Hat Enterprise Linux 10) - Affected
Package: rhel10/thunderbird-flatpak (Red Hat Enterprise Linux 10) - Affected
Package: thunderbird (Red Hat Enterprise Linux 10) - Affected
Package:
Mozilla
Mozilla Foundation Security Advisory 2026-57: CVE-2026-12308
vendor_mozilla·CVSS 5.3
CVE-2026-12308 [MEDIUM] Mozilla Foundation Security Advisory 2026-57: CVE-2026-12308
Mozilla Foundation Security Advisory 2026-57
CVE: CVE-2026-12308
Product: Firefox
Impact: high
Fixed in: Firefox 152
Mozilla
Mozilla Foundation Security Advisory 2026-61: CVE-2026-12308
vendor_mozilla·CVSS 5.3
CVE-2026-12308 [MEDIUM] Mozilla Foundation Security Advisory 2026-61: CVE-2026-12308
Mozilla Foundation Security Advisory 2026-61
CVE: CVE-2026-12308
Product: Thunderbird
Impact: high
Fixed in: Thunderbird 140.12
Mozilla
Mozilla Foundation Security Advisory 2026-58: CVE-2026-12308
vendor_mozilla·CVSS 5.3
CVE-2026-12308 [MEDIUM] Mozilla Foundation Security Advisory 2026-58: CVE-2026-12308
Mozilla Foundation Security Advisory 2026-58
CVE: CVE-2026-12308
Product: Firefox ESR
Impact: high
Fixed in: Firefox ESR 140.12
Mozilla
Mozilla Foundation Security Advisory 2026-60: CVE-2026-12308
vendor_mozilla·CVSS 5.3
CVE-2026-12308 [MEDIUM] Mozilla Foundation Security Advisory 2026-60: CVE-2026-12308
Mozilla Foundation Security Advisory 2026-60
CVE: CVE-2026-12308
Product: Thunderbird
Impact: high
Fixed in: Thunderbird 152
No detection rules found.
No public exploits indexed.
2026-06-16
Published