CVE-2026-12304
published 2026-06-16CVE-2026-12304: Same-origin policy bypass in the Networking: Cookies component. This vulnerability was fixed in Firefox 152, Firefox ESR 140.12, Thunderbird 152, and…
PriorityP352critical9.1CVSS 3.1
AVNACLPRNUINSUCHIHAN
EPSS
0.19%
8.7th percentile
Same-origin policy bypass in the Networking: Cookies component. This vulnerability was fixed in Firefox 152, Firefox ESR 140.12, Thunderbird 152, and Thunderbird 140.12.
Affected
8 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| mozilla | firefox | < Firefox 152 | Firefox 152 |
| mozilla | firefox | — | — |
| 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 | — | — |
| rhel10 | firefox-flatpak | — | — |
| rhel10 | thunderbird-flatpak | — | — |
CVSS provenance
nvdv3.19.1CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
vendor_redhat9.1CRITICAL
Stop checking back — get the weekly exploitation signal.
Every Monday: what got weaponized or added to CISA KEV in the last seven days — each CVE cross-linked to its PoC, Nuclei template, and detection rule. Free, one email a week, unsubscribe in one click.
VulDB
Mozilla Firefox up to 151 Cookies cross-domain policy (Nessus ID 321490)
vuldb·2026-06-18·CVSS 9.1
CVE-2026-12304 [CRITICAL] Mozilla Firefox up to 151 Cookies cross-domain policy (Nessus ID 321490)
A vulnerability labeled as problematic has been found in Mozilla Firefox up to 151. Affected is an unknown function of the component Cookies. The manipulation results in permissive cross-domain policy with untrusted domains.
This vulnerability is cataloged as CVE-2026-12304. The attack may be launched remotely. There is no exploit available.
The affected component should be upgraded.
GHSA
Same-origin policy bypass in the Networking: Cookies component.
ghsa_unreviewed·2026-06-16
CVE-2026-12304 [CRITICAL] CWE-346 Same-origin policy bypass in the Networking: Cookies component.
Same-origin policy bypass in the Networking: Cookies component. This vulnerability was fixed in Firefox 152 and Firefox ESR 140.12.
Red Hat
firefox: thunderbird: Same-origin policy bypass in the Networking: Cookies component
vendor_redhat·2026-06-16·CVSS 9.1
CVE-2026-12304 [CRITICAL] CWE-346 firefox: thunderbird: Same-origin policy bypass in the Networking: Cookies component
firefox: thunderbird: Same-origin policy bypass in the Networking: Cookies component
Same-origin policy bypass in the Networking: Cookies component. 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:
Same-origin policy bypass in the Networking: Cookies 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) - Affected
Package: rhel10/firefox-flatpak (Red Hat Enterprise Linux 10) - Affected
Package: rhel10/thunderbird-flatpak (Red Hat Enterprise Linux 10) - Affected
Package: thunderbird
Mozilla
Mozilla Foundation Security Advisory 2026-60: CVE-2026-12304
vendor_mozilla·CVSS 9.1
CVE-2026-12304 [CRITICAL] Mozilla Foundation Security Advisory 2026-60: CVE-2026-12304
Mozilla Foundation Security Advisory 2026-60
CVE: CVE-2026-12304
Product: Thunderbird
Impact: high
Fixed in: Thunderbird 152
Mozilla
Mozilla Foundation Security Advisory 2026-57: CVE-2026-12304
vendor_mozilla·CVSS 9.1
CVE-2026-12304 [CRITICAL] Mozilla Foundation Security Advisory 2026-57: CVE-2026-12304
Mozilla Foundation Security Advisory 2026-57
CVE: CVE-2026-12304
Product: Firefox
Impact: high
Fixed in: Firefox 152
Mozilla
Mozilla Foundation Security Advisory 2026-58: CVE-2026-12304
vendor_mozilla·CVSS 9.1
CVE-2026-12304 [CRITICAL] Mozilla Foundation Security Advisory 2026-58: CVE-2026-12304
Mozilla Foundation Security Advisory 2026-58
CVE: CVE-2026-12304
Product: Firefox ESR
Impact: high
Fixed in: Firefox ESR 140.12
Mozilla
Mozilla Foundation Security Advisory 2026-61: CVE-2026-12304
vendor_mozilla·CVSS 9.1
CVE-2026-12304 [CRITICAL] Mozilla Foundation Security Advisory 2026-61: CVE-2026-12304
Mozilla Foundation Security Advisory 2026-61
CVE: CVE-2026-12304
Product: Thunderbird
Impact: high
Fixed in: Thunderbird 140.12
No detection rules found.
No public exploits indexed.
2026-06-16
Published