CVE-2026-2758

EUVD-2026-8480
Use-after-free in the JavaScript: GC component. This vulnerability was fixed in Firefox 148, Firefox ESR 115.33, Firefox ESR 140.8, Thunderbird 148, and Thunderbird 140.8.
ProviderTypeBase ScoreAtk. VectorAtk. ComplexityPriv. RequiredVector
NISTPrimary
9.8 CRITICAL
NETWORK
LOW
NONE
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Base Score
CVSS 3.x
EPSS Score
Percentile: 21%
Affected Products (NVD)
VendorProductVersion
mozillafirefox_esr
𝑥
< 115.33.0
mozillafirefox
𝑥
< 148.0
mozillafirefox_esr
128.0 ≤
𝑥
< 140.8.0
mozillathunderbird_esr
𝑥
< 140.8.0
mozillathunderbird
𝑥
< 148.0
𝑥
= Vulnerable software versions
Debian logo
Debian Releases
Debian Product
Codename
firefox
sid
151.0.1-1
fixed
firefox-esr
bookworm
140.10.2esr-1~deb12u1
fixed
bookworm (security)
140.11.0esr-1~deb12u1
fixed
bullseye
vulnerable
bullseye (security)
140.11.0esr-1~deb11u1
fixed
forky
140.11.0esr-1
fixed
sid
140.11.0esr-1
fixed
trixie
140.10.2esr-1~deb13u1
fixed
trixie (security)
140.11.0esr-1~deb13u1
fixed
thunderbird
bookworm
1:140.10.1esr-1~deb12u1
fixed
bookworm (security)
1:140.11.0esr-1~deb12u1
fixed
bullseye
vulnerable
bullseye (security)
1:140.11.0esr-1~deb11u1
fixed
forky
1:140.11.0esr-1
fixed
sid
1:140.11.0esr-1
fixed
trixie
1:140.10.1esr-1~deb13u1
fixed
trixie (security)
1:140.11.0esr-1~deb13u1
fixed
openSUSE logo
openSUSE / SLES Releases
openSUSE Product
Release
MozillaFirefox
suse enterprise desktop 15 SP7
140.8.0-150200.152.222.1
fixed
suse enterprise sap 15 SP4
140.8.0-150200.152.222.1
fixed
suse enterprise sap 15 SP5
140.8.0-150200.152.222.1
fixed
suse enterprise sap 15 SP6
140.8.0-150200.152.222.1
fixed
suse enterprise sap 15 SP7
140.8.0-150200.152.222.1
fixed
suse enterprise server 12 SP3
140.8.0-112.301.1
fixed
suse enterprise server 12 SP5
140.8.0-112.301.1
fixed
suse enterprise server 15 SP4
140.8.0-150200.152.222.1
fixed
suse enterprise server 15 SP5
140.8.0-150200.152.222.1
fixed
suse enterprise server 15 SP6
140.8.0-150200.152.222.1
fixed
suse enterprise server 15 SP7
140.8.0-150200.152.222.1
fixed
MozillaFirefox-devel
suse enterprise desktop 15 SP7
140.8.0-150200.152.222.1
fixed
suse enterprise sap 15 SP4
140.8.0-150200.152.222.1
fixed
suse enterprise sap 15 SP5
140.8.0-150200.152.222.1
fixed
suse enterprise sap 15 SP6
140.8.0-150200.152.222.1
fixed
suse enterprise sap 15 SP7
140.8.0-150200.152.222.1
fixed
suse enterprise server 12 SP3
140.8.0-112.301.1
fixed
suse enterprise server 12 SP5
140.8.0-112.301.1
fixed
suse enterprise server 15 SP4
140.8.0-150200.152.222.1
fixed
suse enterprise server 15 SP5
140.8.0-150200.152.222.1
fixed
suse enterprise server 15 SP6
140.8.0-150200.152.222.1
fixed
suse enterprise server 15 SP7
140.8.0-150200.152.222.1
fixed
MozillaFirefox-translations-common
suse enterprise desktop 15 SP7
140.8.0-150200.152.222.1
fixed
suse enterprise sap 15 SP4
140.8.0-150200.152.222.1
fixed
suse enterprise sap 15 SP5
140.8.0-150200.152.222.1
fixed
suse enterprise sap 15 SP6
140.8.0-150200.152.222.1
fixed
suse enterprise sap 15 SP7
140.8.0-150200.152.222.1
fixed
suse enterprise server 12 SP3
140.8.0-112.301.1
fixed
suse enterprise server 12 SP5
140.8.0-112.301.1
fixed
suse enterprise server 15 SP4
140.8.0-150200.152.222.1
fixed
suse enterprise server 15 SP5
140.8.0-150200.152.222.1
fixed
suse enterprise server 15 SP6
140.8.0-150200.152.222.1
fixed
suse enterprise server 15 SP7
140.8.0-150200.152.222.1
fixed
MozillaFirefox-translations-other
suse enterprise desktop 15 SP7
140.8.0-150200.152.222.1
fixed
suse enterprise sap 15 SP4
140.8.0-150200.152.222.1
fixed
suse enterprise sap 15 SP5
140.8.0-150200.152.222.1
fixed
suse enterprise sap 15 SP6
140.8.0-150200.152.222.1
fixed
suse enterprise sap 15 SP7
140.8.0-150200.152.222.1
fixed
suse enterprise server 15 SP4
140.8.0-150200.152.222.1
fixed
suse enterprise server 15 SP5
140.8.0-150200.152.222.1
fixed
suse enterprise server 15 SP6
140.8.0-150200.152.222.1
fixed
suse enterprise server 15 SP7
140.8.0-150200.152.222.1
fixed
MozillaThunderbird
suse enterprise desktop 15 SP7
140.8.0-150200.8.260.1
fixed
suse enterprise sap 15 SP7
140.8.0-150200.8.260.1
fixed
suse enterprise server 15 SP7
140.8.0-150200.8.260.1
fixed
suse enterprise workstation 15 SP7
140.8.0-150200.8.260.1
fixed
MozillaThunderbird-translations-common
suse enterprise desktop 15 SP7
140.8.0-150200.8.260.1
fixed
suse enterprise sap 15 SP7
140.8.0-150200.8.260.1
fixed
suse enterprise server 15 SP7
140.8.0-150200.8.260.1
fixed
suse enterprise workstation 15 SP7
140.8.0-150200.8.260.1
fixed
MozillaThunderbird-translations-other
suse enterprise desktop 15 SP7
140.8.0-150200.8.260.1
fixed
suse enterprise sap 15 SP7
140.8.0-150200.8.260.1
fixed
suse enterprise server 15 SP7
140.8.0-150200.8.260.1
fixed
suse enterprise workstation 15 SP7
140.8.0-150200.8.260.1
fixed
Red Hat logo
Red Hat Enterprise Linux Releases
Red Hat Product
Release
firefox
RHEL 9
0:140.8.0-2.el9_7
fixed
firefox-x11
RHEL 9
0:140.8.0-2.el9_7
fixed
thunderbird
RHEL 9
0:140.8.0-1.el9_7
fixed
Common Weakness Enumeration
References
https://bugzilla.mozilla.org/show_bug.cgi?id=2009608
https://www.mozilla.org/security/advisories/mfsa2026-13/
https://www.mozilla.org/security/advisories/mfsa2026-14/
https://www.mozilla.org/security/advisories/mfsa2026-15/
https://www.mozilla.org/security/advisories/mfsa2026-16/
https://www.mozilla.org/security/advisories/mfsa2026-17/