CVE-2026-12329
published 2026-06-16CVE-2026-12329: Memory safety bug fixed in Thunderbird ESR 140.12. This vulnerability was fixed in Firefox ESR 140.12 and Thunderbird 140.12.
PriorityP427medium5.3CVSS 3.1
AVNACLPRNUINSUCNINAL
EPSS
0.33%
24.5th percentile
Memory safety bug fixed in Thunderbird ESR 140.12. This vulnerability was fixed in Firefox ESR 140.12 and Thunderbird 140.12.
Affected
8 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| 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 140.12 | Thunderbird 140.12 |
| mozilla | thunderbird | — | — |
| mozilla | thunderbird | >= 140.0 < 140.12.0 | 140.12.0 |
| rhel10 | firefox-flatpak | — | — |
| rhel10 | thunderbird-flatpak | — | — |
CVSS provenance
nvdv3.15.3MEDIUMCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
vendor_redhat5.3MEDIUM
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Red Hat
firefox: thunderbird: Memory safety bug fixed in Thunderbird ESR 140.12
vendor_redhat·2026-06-16·CVSS 5.3
CVE-2026-12329 [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 Thunderbird ESR 140.12. This vulnerability was fixed in Firefox ESR 140.12 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: firefox (Red Hat En
Mozilla
Mozilla Foundation Security Advisory 2026-61: CVE-2026-12329
vendor_mozilla·CVSS 5.3
CVE-2026-12329 [MEDIUM] Mozilla Foundation Security Advisory 2026-61: CVE-2026-12329
Mozilla Foundation Security Advisory 2026-61
CVE: CVE-2026-12329
Product: Thunderbird
Impact: high
Fixed in: Thunderbird 140.12
Mozilla
Mozilla Foundation Security Advisory 2026-58: CVE-2026-12329
vendor_mozilla·CVSS 5.3
CVE-2026-12329 [MEDIUM] Mozilla Foundation Security Advisory 2026-58: CVE-2026-12329
Mozilla Foundation Security Advisory 2026-58
CVE: CVE-2026-12329
Product: Firefox ESR
Impact: high
Fixed in: Firefox ESR 140.12
VulDB
Mozilla Firefox up to 140.11 memory corruption (Nessus ID 321490 / WID-SEC-2026-1959)
vuldb·2026-07-03·CVSS 5.3
CVE-2026-12329 [MEDIUM] Mozilla Firefox up to 140.11 memory corruption (Nessus ID 321490 / WID-SEC-2026-1959)
A vulnerability identified as critical has been detected in Mozilla Firefox up to 140.11. This issue affects some unknown processing. Performing a manipulation results in memory corruption.
This vulnerability is identified as CVE-2026-12329. The attack can be initiated remotely. There is not any exploit available.
You should upgrade the affected component.
GHSA
Memory safety bug fixed in Firefox ESR 140.12.
ghsa_unreviewed·2026-06-16
CVE-2026-12329 [MEDIUM] CWE-119 Memory safety bug fixed in Firefox ESR 140.12.
Memory safety bug fixed in Firefox ESR 140.12. This vulnerability was fixed in Firefox ESR 140.12.
No detection rules found.
No public exploits indexed.
https://bugzilla.mozilla.org/show_bug.cgi?id=2044738https://www.mozilla.org/security/advisories/mfsa2026-58/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-2026-12329https://bugzilla.redhat.com/show_bug.cgi?id=2489214https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-12329.json
2026-06-16
Published