CVE-2026-3846

EUVD-2026-10504
Same-origin policy bypass in the CSS Parsing and Computation component. This vulnerability affects Firefox < 148.0.2.
ProviderTypeBase ScoreAtk. VectorAtk. ComplexityPriv. RequiredVector
NISTPrimary
6.5 MEDIUM
NETWORK
LOW
NONE
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N
CISA-ADPADP
6.5 MEDIUM
NETWORK
LOW
NONE
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N
Base Score
CVSS 3.x
EPSS Score
Percentile: Unknown
Affected Products (NVD)
VendorProductVersion
mozillafirefox
𝑥
< 148.0.2
𝑥
= Vulnerable software versions
Debian logo
Debian Releases
Debian Product
Codename
firefox
sid
148.0.2-1
fixed
Ubuntu logo
Ubuntu Releases
Ubuntu Product
Codename
firefox
jammy
not-affected
noble
not-affected
questing
not-affected
thunderbird
jammy
needed
noble
not-affected
questing
not-affected
mozjs38
bionic
needs-triage
jammy
dne
noble
dne
questing
dne
mozjs52
bionic
ignored
focal
ignored
jammy
dne
noble
dne
questing
dne
mozjs68
focal
ignored
jammy
dne
noble
dne
questing
dne
mozjs78
jammy
ignored
noble
dne
questing
dne
mozjs91
jammy
ignored
noble
dne
questing
dne
mozjs102
jammy
ignored
noble
ignored
questing
dne
mozjs115
jammy
dne
noble
ignored
questing
dne
Common Weakness Enumeration
References
https://bugzilla.mozilla.org/show_bug.cgi?id=2018400
https://www.mozilla.org/security/advisories/mfsa2026-19/