CVE-2026-12323
published 2026-06-16CVE-2026-12323: Spoofing issue in the DOM: Core & HTML component. This vulnerability was fixed in Firefox 152 and Thunderbird 152.
PriorityP423medium5.4CVSS 3.1
AVNACLPRNUIRSUCLINAL
EPSS
0.17%
6.4th percentile
Spoofing issue in the DOM: Core & HTML component. This vulnerability was fixed in Firefox 152 and Thunderbird 152.
Affected
4 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| mozilla | firefox | < Firefox 152 | Firefox 152 |
| mozilla | firefox | < 152.0.0 | 152.0.0 |
| mozilla | thunderbird | < Thunderbird 152 | Thunderbird 152 |
| mozilla | thunderbird | < 152.0.0 | 152.0.0 |
CVSS provenance
nvdv3.15.4MEDIUMCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:L
vendor_redhat5.4MEDIUM
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VulDB
Mozilla Firefox up to 151 HTML ui layer (EUVD-2026-37069 / Nessus ID 321384)
vuldb·2026-07-10·CVSS 5.4
CVE-2026-12323 [MEDIUM] Mozilla Firefox up to 151 HTML ui layer (EUVD-2026-37069 / Nessus ID 321384)
A vulnerability was found in Mozilla Firefox up to 151. It has been declared as problematic. Affected by this issue is some unknown functionality of the component HTML. The manipulation results in improper restriction of rendered ui layers.
This vulnerability was named CVE-2026-12323. The attack may be performed from remote. There is no available exploit.
It is recommended to upgrade the affected component.
GHSA
Spoofing issue in the DOM: Core & HTML component.
ghsa_unreviewed·2026-06-16
CVE-2026-12323 [MEDIUM] CWE-1021 Spoofing issue in the DOM: Core & HTML component.
Spoofing issue in the DOM: Core & HTML component. This vulnerability was fixed in Firefox 152.
Red Hat
firefox: thunderbird: Spoofing issue in the DOM: Core & HTML component
vendor_redhat·2026-06-16·CVSS 5.4
CVE-2026-12323 [MEDIUM] CWE-1021 firefox: thunderbird: Spoofing issue in the DOM: Core & HTML component
firefox: thunderbird: Spoofing issue in the DOM: Core & HTML component
Spoofing issue in the DOM: Core & HTML component. This vulnerability was fixed in Firefox 152 and Thunderbird 152.
A flaw was found in Firefox and Thunderbird. The Mozilla Foundation's Security Advisory describes the following issue:
Spoofing issue in the DOM: Core & HTML component
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) - Not affected
Package: rhel10/firefox-flatpak (Red Hat Enterprise Linux 10) - Not affected
Package: rhel10/thunderbird-flatpak (Red Hat Enterprise Linux 10) - Not affected
Package: thunderbird (Red Hat Enterprise Linux 10) - Not affected
Package: firefox (Red Hat
Mozilla
Mozilla Foundation Security Advisory 2026-57: CVE-2026-12323
vendor_mozilla·CVSS 5.4
CVE-2026-12323 [MEDIUM] Mozilla Foundation Security Advisory 2026-57: CVE-2026-12323
Mozilla Foundation Security Advisory 2026-57
CVE: CVE-2026-12323
Product: Firefox
Impact: high
Fixed in: Firefox 152
Mozilla
Mozilla Foundation Security Advisory 2026-60: CVE-2026-12323
vendor_mozilla·CVSS 5.4
CVE-2026-12323 [MEDIUM] Mozilla Foundation Security Advisory 2026-60: CVE-2026-12323
Mozilla Foundation Security Advisory 2026-60
CVE: CVE-2026-12323
Product: Thunderbird
Impact: high
Fixed in: Thunderbird 152
No detection rules found.
No public exploits indexed.
2026-06-16
Published