CVE-2026-74942
published 2026-08-18CVE-2026-74942: Privilege escalation in the Remote Settings Client component. This vulnerability was fixed in Firefox 154, Firefox ESR 115.39, Firefox ESR 140.14, Firefox ESR…
PriorityP349high8.8CVSS 3.1
AVNACLPRNUIRSUCHIHAH
EPSS
0.30%
22.4th percentile
Privilege escalation in the Remote Settings Client component. This vulnerability was fixed in Firefox 154, Firefox ESR 115.39, Firefox ESR 140.14, Firefox ESR 153.1, Thunderbird 154, Thunderbird 140.14, and Thunderbird 153.1.
Affected
16 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| mozilla | firefox | < Firefox 154 | Firefox 154 |
| mozilla | firefox | < 115.39.0 | 115.39.0 |
| mozilla | firefox | — | — |
| mozilla | firefox | >= 116.0 < 140.14.0 | 140.14.0 |
| mozilla | firefox | >= 141.0 < 153.1.0 | 153.1.0 |
| mozilla | firefox_esr | < Firefox ESR 153.1 | Firefox ESR 153.1 |
| mozilla | firefox_esr | < Firefox ESR 140.14 | Firefox ESR 140.14 |
| mozilla | firefox_esr | < Firefox ESR 115.39 | Firefox ESR 115.39 |
| mozilla | thunderbird | < Thunderbird 153.1 | Thunderbird 153.1 |
| mozilla | thunderbird | < Thunderbird 154 | Thunderbird 154 |
| mozilla | thunderbird | < Thunderbird 140.14 | Thunderbird 140.14 |
| mozilla | thunderbird | < 140.14.0 | 140.14.0 |
| mozilla | thunderbird | — | — |
| mozilla | thunderbird | >= 141.0 < 153.1.0 | 153.1.0 |
| rhel10 | firefox-flatpak | — | — |
| rhel10 | thunderbird-flatpak | — | — |
CVSS provenance
nvdv3.18.8HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
vendor_redhat8.8HIGH
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.
Red Hat
firefox: Privilege escalation in the Remote Settings Client component
vendor_redhat·2026-08-18·CVSS 8.8
CVE-2026-74942 [HIGH] CWE-266 firefox: Privilege escalation in the Remote Settings Client component
firefox: Privilege escalation in the Remote Settings Client component
A flaw was found in Firefox. The Mozilla Foundation's Security Advisory describes the following issue:
Privilege escalation in the Remote Settings Client 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 (Red Hat Enterprise Linux 10) - Affected
Package: firefox (Red Hat Enterprise Linux 6) - Out of support scope
Package: thunderbird (Red Hat Enterprise Linux 6) - Out of support scope
Package: firefox (
Mozilla
Mozilla Foundation Security Advisory 2026-80: CVE-2026-74942
vendor_mozilla
CVE-2026-74942 Mozilla Foundation Security Advisory 2026-80: CVE-2026-74942
Mozilla Foundation Security Advisory 2026-80
CVE: CVE-2026-74942
Product: Thunderbird
Impact: high
Fixed in: Thunderbird 153.1
Mozilla
Mozilla Foundation Security Advisory 2026-77: CVE-2026-74942
vendor_mozilla
CVE-2026-74942 Mozilla Foundation Security Advisory 2026-77: CVE-2026-74942
Mozilla Foundation Security Advisory 2026-77
CVE: CVE-2026-74942
Product: Firefox ESR
Impact: high
Fixed in: Firefox ESR 153.1
Mozilla
Mozilla Foundation Security Advisory 2026-78: CVE-2026-74942
vendor_mozilla
CVE-2026-74942 Mozilla Foundation Security Advisory 2026-78: CVE-2026-74942
Mozilla Foundation Security Advisory 2026-78
CVE: CVE-2026-74942
Product: Thunderbird
Impact: high
Fixed in: Thunderbird 154
Mozilla
Mozilla Foundation Security Advisory 2026-76: CVE-2026-74942
vendor_mozilla
CVE-2026-74942 Mozilla Foundation Security Advisory 2026-76: CVE-2026-74942
Mozilla Foundation Security Advisory 2026-76
CVE: CVE-2026-74942
Product: Firefox ESR
Impact: high
Fixed in: Firefox ESR 140.14
Mozilla
Mozilla Foundation Security Advisory 2026-75: CVE-2026-74942
vendor_mozilla
CVE-2026-74942 Mozilla Foundation Security Advisory 2026-75: CVE-2026-74942
Mozilla Foundation Security Advisory 2026-75
CVE: CVE-2026-74942
Product: Firefox ESR
Impact: high
Fixed in: Firefox ESR 115.39
Mozilla
Mozilla Foundation Security Advisory 2026-74: CVE-2026-74942
vendor_mozilla
CVE-2026-74942 Mozilla Foundation Security Advisory 2026-74: CVE-2026-74942
Mozilla Foundation Security Advisory 2026-74
CVE: CVE-2026-74942
Product: Firefox
Impact: high
Fixed in: Firefox 154
Mozilla
Mozilla Foundation Security Advisory 2026-79: CVE-2026-74942
vendor_mozilla
CVE-2026-74942 Mozilla Foundation Security Advisory 2026-79: CVE-2026-74942
Mozilla Foundation Security Advisory 2026-79
CVE: CVE-2026-74942
Product: Thunderbird
Impact: high
Fixed in: Thunderbird 140.14
VulDB
Mozilla Firefox up to 115.38/140.13/153/153.0 Remote Settings Client privileges management
vuldb·2026-08-23·CVSS 8.8
CVE-2026-74942 [HIGH] Mozilla Firefox up to 115.38/140.13/153/153.0 Remote Settings Client privileges management
A vulnerability has been found in Mozilla Firefox up to 115.38/140.13/153/153.0 and classified as critical. Impacted is an unknown function of the component Remote Settings Client. The manipulation leads to improper privilege management.
This vulnerability is listed as CVE-2026-74942. The attack may be initiated remotely. There is no available exploit.
The affected component should be upgraded.
GHSA
Privilege escalation in the Remote Settings Client component.
ghsa_unreviewed·2026-08-18
CVE-2026-74942 [HIGH] CWE-269 Privilege escalation in the Remote Settings Client component.
Privilege escalation in the Remote Settings Client component. This vulnerability was fixed in Firefox 154, Firefox ESR 115.39, Firefox ESR 140.14, and Firefox ESR 153.1.
No detection rules found.
No public exploits indexed.
https://bugzilla.mozilla.org/show_bug.cgi?id=2056571https://www.mozilla.org/security/advisories/mfsa2026-74/https://www.mozilla.org/security/advisories/mfsa2026-75/https://www.mozilla.org/security/advisories/mfsa2026-76/https://www.mozilla.org/security/advisories/mfsa2026-77/https://www.mozilla.org/security/advisories/mfsa2026-78/https://www.mozilla.org/security/advisories/mfsa2026-79/https://www.mozilla.org/security/advisories/mfsa2026-80/
2026-08-18
Published