CVE-2026-84133
published 2026-09-01CVE-2026-84133: Site isolation issue in the DOM: Push Subscriptions component. This vulnerability was fixed in Firefox 155, Firefox ESR 153.2, Thunderbird 155, and Thunderbird…
PriorityP352critical9.8CVSS 3.1
AVNACLPRNUINSUCHIHAH
EPSS
0.18%
7.7th percentile
Site isolation issue in the DOM: Push Subscriptions component. This vulnerability was fixed in Firefox 155, Firefox ESR 153.2, Thunderbird 155, and Thunderbird 153.2.
Affected
8 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| mozilla | firefox | < Firefox 155 | Firefox 155 |
| mozilla | firefox | < 153.2.0 | 153.2.0 |
| mozilla | firefox | >= 154.0.0 < 155.0.0 | 155.0.0 |
| mozilla | firefox_esr | < Firefox ESR 153.2 | Firefox ESR 153.2 |
| mozilla | thunderbird | < Thunderbird 153.2 | Thunderbird 153.2 |
| mozilla | thunderbird | < Thunderbird 155 | Thunderbird 155 |
| mozilla | thunderbird | < 153.2.0 | 153.2.0 |
| mozilla | thunderbird | >= 154.0 < 155.0 | 155.0 |
CVSS provenance
nvdv3.19.8CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
vendor_redhat9.8CRITICAL
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Red Hat
firefox: thunderbird: Site isolation issue in the DOM: Push Subscriptions component
vendor_redhat·2026-09-01·CVSS 9.8
CVE-2026-84133 [CRITICAL] CWE-653 firefox: thunderbird: Site isolation issue in the DOM: Push Subscriptions component
firefox: thunderbird: Site isolation issue in the DOM: Push Subscriptions component
Site isolation issue in the DOM: Push Subscriptions component. This vulnerability was fixed in Firefox 155, Firefox ESR 153.2, Thunderbird 155, and Thunderbird 153.2.
A flaw was found in Firefox and Thunderbird. The Mozilla Foundation's Security Advisory describes the following issue:
Site isolation issue in the DOM: Push Subscriptions 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: thund
Mozilla
Mozilla Foundation Security Advisory 2026-82: CVE-2026-84133
vendor_mozilla
CVE-2026-84133 Mozilla Foundation Security Advisory 2026-82: CVE-2026-84133
Mozilla Foundation Security Advisory 2026-82
CVE: CVE-2026-84133
Product: Firefox
Impact: high
Fixed in: Firefox 155
Mozilla
Mozilla Foundation Security Advisory 2026-85: CVE-2026-84133
vendor_mozilla
CVE-2026-84133 Mozilla Foundation Security Advisory 2026-85: CVE-2026-84133
Mozilla Foundation Security Advisory 2026-85
CVE: CVE-2026-84133
Product: Firefox ESR
Impact: high
Fixed in: Firefox ESR 153.2
Mozilla
Mozilla Foundation Security Advisory 2026-88: CVE-2026-84133
vendor_mozilla
CVE-2026-84133 Mozilla Foundation Security Advisory 2026-88: CVE-2026-84133
Mozilla Foundation Security Advisory 2026-88
CVE: CVE-2026-84133
Product: Thunderbird
Impact: high
Fixed in: Thunderbird 153.2
Mozilla
Mozilla Foundation Security Advisory 2026-86: CVE-2026-84133
vendor_mozilla
CVE-2026-84133 Mozilla Foundation Security Advisory 2026-86: CVE-2026-84133
Mozilla Foundation Security Advisory 2026-86
CVE: CVE-2026-84133
Product: Thunderbird
Impact: high
Fixed in: Thunderbird 155
VulDB
Mozilla Firefox up to 153.1/154 Push Subscriptions isolation (Nessus ID 342305)
vuldb·2026-09-03
CVE-2026-84133 [CRITICAL] Mozilla Firefox up to 153.1/154 Push Subscriptions isolation (Nessus ID 342305)
A vulnerability identified as critical has been detected in Mozilla Firefox up to 153.1/154. This vulnerability affects unknown code of the component Push Subscriptions. This manipulation causes improper isolation or compartmentalization.
The identification of this vulnerability is CVE-2026-84133. It is possible to initiate the attack remotely. There is no exploit available.
You should upgrade the affected component.
GHSA
Site isolation issue in the DOM: Push Subscriptions component.
ghsa_unreviewed·2026-09-01
CVE-2026-84133 Site isolation issue in the DOM: Push Subscriptions component.
Site isolation issue in the DOM: Push Subscriptions component. This vulnerability was fixed in Firefox 155 and Firefox ESR 153.2.
No detection rules found.
No public exploits indexed.
2026-09-01
Published