CVE-2026-12298
published 2026-06-16CVE-2026-12298: Memory safety bug fixed in Firefox 152. This vulnerability was fixed in Firefox 152, Firefox ESR 140.12, Thunderbird 152, and Thunderbird 140.12.
PriorityP426medium5.4CVSS 3.1
AVNACLPRNUIRSUCLILAN
EPSS
0.31%
22.4th percentile
Memory safety bug fixed in Firefox 152. This vulnerability was fixed in Firefox 152, Firefox ESR 140.12, Thunderbird 152, and Thunderbird 140.12.
Affected
12 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| mozilla | firefox | < Firefox 152 | Firefox 152 |
| mozilla | firefox | < 152.0 | 152.0 |
| mozilla | firefox | — | — |
| mozilla | firefox | >= 140.0 < 140.12.0 | 140.12.0 |
| mozilla | firefox_esr | < Firefox ESR 140.12 | Firefox ESR 140.12 |
| mozilla | thunderbird | < Thunderbird 152 | Thunderbird 152 |
| mozilla | thunderbird | < Thunderbird 140.12 | Thunderbird 140.12 |
| mozilla | thunderbird | < 152.0.0 | 152.0.0 |
| mozilla | thunderbird | — | — |
| mozilla | thunderbird | >= 140.0 < 140.12.0 | 140.12.0 |
| rhel10 | firefox-flatpak | — | — |
| rhel10 | thunderbird-flatpak | — | — |
CVSS provenance
nvdv3.15.4MEDIUMCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N
vendor_redhat5.4MEDIUM
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VulDB
Mozilla Firefox up to 151 memory corruption (Nessus ID 321490 / WID-SEC-2026-1959)
vuldb·2026-07-03·CVSS 5.4
CVE-2026-12298 [MEDIUM] Mozilla Firefox up to 151 memory corruption (Nessus ID 321490 / WID-SEC-2026-1959)
A vulnerability was found in Mozilla Firefox up to 151. It has been rated as critical. The impacted element is an unknown function. Performing a manipulation results in memory corruption.
This vulnerability is identified as CVE-2026-12298. The attack can be initiated remotely. There is not any exploit available.
Upgrading the affected component is advised.
GHSA
Memory safety bug fixed in Firefox 152.
ghsa_unreviewed·2026-06-16
CVE-2026-12298 [MEDIUM] CWE-125 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 Firefox ESR 140.12
vendor_redhat·2026-06-16·CVSS 5.4
CVE-2026-12298 [MEDIUM] CWE-843 firefox: thunderbird: Memory safety bug fixed in Firefox ESR 140.12
firefox: thunderbird: Memory safety bug fixed in Firefox 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 Firefox 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: firefox
Mozilla
Mozilla Foundation Security Advisory 2026-58: CVE-2026-12298
vendor_mozilla·CVSS 5.4
CVE-2026-12298 [MEDIUM] Mozilla Foundation Security Advisory 2026-58: CVE-2026-12298
Mozilla Foundation Security Advisory 2026-58
CVE: CVE-2026-12298
Product: Firefox ESR
Impact: high
Fixed in: Firefox ESR 140.12
Mozilla
Mozilla Foundation Security Advisory 2026-57: CVE-2026-12298
vendor_mozilla·CVSS 5.4
CVE-2026-12298 [MEDIUM] Mozilla Foundation Security Advisory 2026-57: CVE-2026-12298
Mozilla Foundation Security Advisory 2026-57
CVE: CVE-2026-12298
Product: Firefox
Impact: high
Fixed in: Firefox 152
Mozilla
Mozilla Foundation Security Advisory 2026-60: CVE-2026-12298
vendor_mozilla·CVSS 5.4
CVE-2026-12298 [MEDIUM] Mozilla Foundation Security Advisory 2026-60: CVE-2026-12298
Mozilla Foundation Security Advisory 2026-60
CVE: CVE-2026-12298
Product: Thunderbird
Impact: high
Fixed in: Thunderbird 152
Mozilla
Mozilla Foundation Security Advisory 2026-61: CVE-2026-12298
vendor_mozilla·CVSS 5.4
CVE-2026-12298 [MEDIUM] Mozilla Foundation Security Advisory 2026-61: CVE-2026-12298
Mozilla Foundation Security Advisory 2026-61
CVE: CVE-2026-12298
Product: Thunderbird
Impact: high
Fixed in: Thunderbird 140.12
No detection rules found.
No public exploits indexed.
https://bugzilla.mozilla.org/show_bug.cgi?id=2041981https://www.mozilla.org/security/advisories/mfsa2026-57/https://www.mozilla.org/security/advisories/mfsa2026-58/https://www.mozilla.org/security/advisories/mfsa2026-60/https://www.mozilla.org/security/advisories/mfsa2026-61/https://access.redhat.com/errata/RHSA-2026:27717https://access.redhat.com/errata/RHSA-2026:27733https://access.redhat.com/errata/RHSA-2026:27734https://access.redhat.com/errata/RHSA-2026:29940https://access.redhat.com/errata/RHSA-2026:30846https://access.redhat.com/errata/RHSA-2026:33445https://access.redhat.com/errata/RHSA-2026:36100https://access.redhat.com/errata/RHSA-2026:36101https://access.redhat.com/errata/RHSA-2026:36102https://access.redhat.com/errata/RHSA-2026:36103https://access.redhat.com/errata/RHSA-2026:37210https://access.redhat.com/errata/RHSA-2026:37391https://access.redhat.com/errata/RHSA-2026:38506https://access.redhat.com/errata/RHSA-2026:38750https://access.redhat.com/errata/RHSA-2026:38751https://access.redhat.com/errata/RHSA-2026:38753https://access.redhat.com/security/cve/CVE-2026-12298https://bugzilla.redhat.com/show_bug.cgi?id=2489248https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-12298.json
2026-06-16
Published