--- id: CVE-2026-92019 title: Mitigation bypass in the Remote Settings Client component summary: >- Mitigation bypass in the Remote Settings Client component. This vulnerability was fixed in Firefox 156, Firefox ESR 115.41, Firefox ESR 140.16, Firefox ESR 153.3, Thunderbird 156, Thunderbird 140.16, and Thunderbird 153.3. severity: high cvss: 8.1 cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:N' cwe: - CWE-693 - CWE-807 vendor: mozilla product: firefox affected: - firefox < 115.41.0 - 'firefox >= 116.0, < 140.16.0' - 'firefox >= 141.0, < 153.3.0' - 'firefox >= 154.0.0, < 156.0.0' - thunderbird < 140.16.0 - 'thunderbird >= 141.0, < 153.3.0' - 'thunderbird >= 154.0, < 156.0' patched: - firefox 156.0.0 - thunderbird 156.0 published: '2026-09-15' updated: '2026-10-06' sourceUpdated: '2026-10-06T14:40:12.207' source: NVD sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-92019' references: - url: 'https://bugzilla.mozilla.org/show_bug.cgi?id=2065636' label: security@mozilla.org - url: 'https://www.mozilla.org/security/advisories/mfsa2026-90/' label: security@mozilla.org - url: 'https://www.mozilla.org/security/advisories/mfsa2026-91/' label: security@mozilla.org - url: 'https://www.mozilla.org/security/advisories/mfsa2026-92/' label: security@mozilla.org - url: 'https://www.mozilla.org/security/advisories/mfsa2026-93/' label: security@mozilla.org - url: 'https://www.mozilla.org/security/advisories/mfsa2026-94/' label: security@mozilla.org - url: 'https://www.mozilla.org/security/advisories/mfsa2026-95/' label: security@mozilla.org - url: 'https://www.mozilla.org/security/advisories/mfsa2026-96/' label: security@mozilla.org - url: >- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-92019.json - url: 'https://access.redhat.com/security/cve/CVE-2026-92019' - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2533740' - url: 'https://www.cve.org/CVERecord?id=CVE-2026-92019' - url: 'https://nvd.nist.gov/vuln/detail/CVE-2026-92019' - url: 'https://www.mozilla.org/security/advisories/mfsa2026-92/#CVE-2026-92019' - url: 'https://www.mozilla.org/security/advisories/mfsa2026-95/#CVE-2026-92019' - url: 'https://access.redhat.com/errata/RHSA-2026:69461' - url: 'https://access.redhat.com/errata/RHSA-2026:69462' - url: 'https://access.redhat.com/errata/RHSA-2026:70642' - url: 'https://access.redhat.com/errata/RHSA-2026:71652' - url: 'https://access.redhat.com/errata/RHSA-2026:73130' - url: 'https://access.redhat.com/errata/RHSA-2026:73971' - url: 'https://access.redhat.com/errata/RHSA-2026:82818' - url: 'https://access.redhat.com/errata/RHSA-2026:81392' - url: 'https://access.redhat.com/errata/RHSA-2026:82122' - url: 'https://access.redhat.com/errata/RHSA-2026:81913' - url: 'https://access.redhat.com/errata/RHSA-2026:82720' - url: 'https://access.redhat.com/errata/RHSA-2026:81912' - url: 'https://access.redhat.com/errata/RHSA-2026:82780' - url: 'https://access.redhat.com/errata/RHSA-2026:81394' - url: 'https://access.redhat.com/errata/RHSA-2026:81393' - url: 'https://access.redhat.com/errata/RHSA-2026:82817' - url: 'https://access.redhat.com/errata/RHSA-2026:81884' - url: 'https://access.redhat.com/errata/RHSA-2026:83496' - url: 'https://access.redhat.com/errata/RHSA-2026:82779' - url: 'https://access.redhat.com/errata/RHSA-2026:83076' - url: 'https://access.redhat.com/errata/RHSA-2026:83077' tags: - nvd - cve.org - csaf - vex - red-hat epss: 0.00307 epssPercentile: 0.23413 ssvc: exploitation: none automatable: 'no' technicalImpact: total timestamp: '2026-09-21T16:45:25.729934Z' scores: nvd: 8.1 vendor: 7.5 ingestedAt: '2026-09-15T12:36:50.194Z' --- ## Overview Mitigation bypass in the Remote Settings Client component. This vulnerability was fixed in Firefox 156, Firefox ESR 115.41, Firefox ESR 140.16, Firefox ESR 153.3, Thunderbird 156, Thunderbird 140.16, and Thunderbird 153.3. ## Affected - `firefox < 115.41.0` - `firefox >= 116.0, < 140.16.0` - `firefox >= 141.0, < 153.3.0` - `firefox >= 154.0.0, < 156.0.0` - `thunderbird < 140.16.0` - `thunderbird >= 141.0, < 153.3.0` - `thunderbird >= 154.0, < 156.0` ## Remediation Upgrade past the affected range: - `firefox 156.0.0` - `thunderbird 156.0` ## Vendor advisories - **Red Hat VEX** · Important · affected: Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 6, Red Hat Enterprise Linux 7 · no fix planned: Red Hat Enterprise Linux 6, Red Hat Enterprise Linux 7, Red Hat Enterprise Linux 10 · updated 2026-10-15 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-92019.json) - **RHSA-2026:69461** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream (v. 10) · released 2026-09-21 · [advisory](https://access.redhat.com/errata/RHSA-2026:69461) - **RHSA-2026:69462** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream (v. 9) · released 2026-09-21 · [advisory](https://access.redhat.com/errata/RHSA-2026:69462) - **RHSA-2026:70642** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream (v. 9) · released 2026-09-24 · [advisory](https://access.redhat.com/errata/RHSA-2026:70642) - **RHSA-2026:71652** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream (v. 8) · released 2026-09-24 · [advisory](https://access.redhat.com/errata/RHSA-2026:71652) - **RHSA-2026:73130** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream (v. 10) · released 2026-09-29 · [advisory](https://access.redhat.com/errata/RHSA-2026:73130) - **RHSA-2026:73971** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream (v. 8) · released 2026-09-30 · [advisory](https://access.redhat.com/errata/RHSA-2026:73971) - **RHSA-2026:82818** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream EUS (v. 10.0) · released 2026-10-14 · [advisory](https://access.redhat.com/errata/RHSA-2026:82818) - **RHSA-2026:81392** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream EUS (v. 10.0) · released 2026-10-12 · [advisory](https://access.redhat.com/errata/RHSA-2026:81392) - **RHSA-2026:82122** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream AUS (v.8.4), Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.4) · released 2026-10-13 · [advisory](https://access.redhat.com/errata/RHSA-2026:82122) - **RHSA-2026:81913** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream AUS (v.8.6), Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.6) · released 2026-10-13 · [advisory](https://access.redhat.com/errata/RHSA-2026:81913) - **RHSA-2026:82720** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream E4S (v.8.8), Red Hat Enterprise Linux AppStream TUS (v.8.8) · released 2026-10-14 · [advisory](https://access.redhat.com/errata/RHSA-2026:82720) - **RHSA-2026:81912** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream E4S (v.8.8), Red Hat Enterprise Linux AppStream TUS (v.8.8) · released 2026-10-13 · [advisory](https://access.redhat.com/errata/RHSA-2026:81912) - **RHSA-2026:82780** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream E4S (v.9.2) · released 2026-10-14 · [advisory](https://access.redhat.com/errata/RHSA-2026:82780) - **RHSA-2026:83496** · Red Hat · fixed in: Red Hat Enterprise Linux Server (v. 7 ELS) · released 2026-10-15 · [advisory](https://access.redhat.com/errata/RHSA-2026:83496) - **RHSA-2026:82779** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream AUS (v.8.4), Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.4) · released 2026-10-14 · [advisory](https://access.redhat.com/errata/RHSA-2026:82779) - **RHSA-2026:83076** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream AUS (v.8.6), Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.6) · released 2026-10-14 · [advisory](https://access.redhat.com/errata/RHSA-2026:83076)