CVE-2026-75874
published 2026-08-18CVE-2026-75874: Sandbox escape in the Remote Settings Client component. This vulnerability was fixed in Firefox 154, Thunderbird 154, Firefox ESR 115.40, Firefox ESR 140.15…
PriorityP357critical10CVSS 3.1
AVNACLPRNUINSCCHIHAH
EPSS
0.46%
38.1th percentile
Sandbox escape in the Remote Settings Client component. This vulnerability was fixed in Firefox 154, Thunderbird 154, Firefox ESR 115.40, Firefox ESR 140.15, Firefox ESR 153.2, Thunderbird 140.15, and Thunderbird 153.2.
Affected
9 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| mozilla | firefox | < Firefox 154 | Firefox 154 |
| mozilla | firefox | < 154.0.0 | 154.0.0 |
| mozilla | firefox_esr | < Firefox ESR 115.40 | Firefox ESR 115.40 |
| mozilla | firefox_esr | < Firefox ESR 140.15 | Firefox ESR 140.15 |
| mozilla | firefox_esr | < Firefox ESR 153.2 | Firefox ESR 153.2 |
| mozilla | thunderbird | < Thunderbird 153.2 | Thunderbird 153.2 |
| mozilla | thunderbird | < Thunderbird 140.15 | Thunderbird 140.15 |
| mozilla | thunderbird | < Thunderbird 154 | Thunderbird 154 |
| mozilla | thunderbird | < 154.0 | 154.0 |
CVSS provenance
nvdv3.110.0CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H
vendor_redhat10.0CRITICAL
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Red Hat
firefox: thunderbird: Sandbox escape in the Remote Settings Client component
vendor_redhat·2026-08-18·CVSS 10.0
CVE-2026-75874 [CRITICAL] CWE-653 firefox: thunderbird: Sandbox escape in the Remote Settings Client component
firefox: thunderbird: Sandbox escape in the Remote Settings Client component
Sandbox escape in the Remote Settings Client component. This vulnerability was fixed in Firefox 154 and Thunderbird 154.
A flaw was found in Firefox and Thunderbird. The Mozilla Foundation's Security Advisory describes the following issue:
Sandbox escape 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) - 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
Mozilla
Mozilla Foundation Security Advisory 2026-88: CVE-2026-75874
vendor_mozilla·CVSS 10.0
CVE-2026-75874 [CRITICAL] Mozilla Foundation Security Advisory 2026-88: CVE-2026-75874
Mozilla Foundation Security Advisory 2026-88
CVE: CVE-2026-75874
Product: Thunderbird
Impact: high
Fixed in: Thunderbird 153.2
Mozilla
Mozilla Foundation Security Advisory 2026-83: CVE-2026-75874
vendor_mozilla·CVSS 10.0
CVE-2026-75874 [CRITICAL] Mozilla Foundation Security Advisory 2026-83: CVE-2026-75874
Mozilla Foundation Security Advisory 2026-83
CVE: CVE-2026-75874
Product: Firefox ESR
Impact: high
Fixed in: Firefox ESR 115.40
Mozilla
Mozilla Foundation Security Advisory 2026-84: CVE-2026-75874
vendor_mozilla·CVSS 10.0
CVE-2026-75874 [CRITICAL] Mozilla Foundation Security Advisory 2026-84: CVE-2026-75874
Mozilla Foundation Security Advisory 2026-84
CVE: CVE-2026-75874
Product: Firefox ESR
Impact: high
Fixed in: Firefox ESR 140.15
Mozilla
Mozilla Foundation Security Advisory 2026-87: CVE-2026-75874
vendor_mozilla·CVSS 10.0
CVE-2026-75874 [CRITICAL] Mozilla Foundation Security Advisory 2026-87: CVE-2026-75874
Mozilla Foundation Security Advisory 2026-87
CVE: CVE-2026-75874
Product: Thunderbird
Impact: high
Fixed in: Thunderbird 140.15
Mozilla
Mozilla Foundation Security Advisory 2026-85: CVE-2026-75874
vendor_mozilla·CVSS 10.0
CVE-2026-75874 [CRITICAL] Mozilla Foundation Security Advisory 2026-85: CVE-2026-75874
Mozilla Foundation Security Advisory 2026-85
CVE: CVE-2026-75874
Product: Firefox ESR
Impact: high
Fixed in: Firefox ESR 153.2
Mozilla
Mozilla Foundation Security Advisory 2026-78: CVE-2026-75874
vendor_mozilla
CVE-2026-75874 Mozilla Foundation Security Advisory 2026-78: CVE-2026-75874
Mozilla Foundation Security Advisory 2026-78
CVE: CVE-2026-75874
Product: Thunderbird
Impact: high
Fixed in: Thunderbird 154
Mozilla
Mozilla Foundation Security Advisory 2026-74: CVE-2026-75874
vendor_mozilla
CVE-2026-75874 Mozilla Foundation Security Advisory 2026-74: CVE-2026-75874
Mozilla Foundation Security Advisory 2026-74
CVE: CVE-2026-75874
Product: Firefox
Impact: high
Fixed in: Firefox 154
GHSA
Sandbox escape in the Remote Settings Client component.
ghsa_unreviewed·2026-08-18
CVE-2026-75874 [CRITICAL] CWE-693 Sandbox escape in the Remote Settings Client component.
Sandbox escape in the Remote Settings Client component. This vulnerability was fixed in Firefox 154.
No detection rules found.
No public exploits indexed.
Hackernews
⚡ Weekly Recap: AI-Powered PLC Attacks, GitLab Attacks, Stripe Key Leaks and More
blogs_hackernews·2026-08-24
CVE-2026-19478 ⚡ Weekly Recap: AI-Powered PLC Attacks, GitLab Attacks, Stripe Key Leaks and More
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## ⚡ Weekly Recap: AI-Powered PLC Attacks, GitLab Attacks, Stripe Key Leaks and More
A package gets installed. A login prompt opens. A box sits exposed to the internet. Nothing looks unusual yet.
That’s roughly the mood this week. Trusted tools turn hostile, old weak spots get fresh attention, AI makes exploit work cheaper, and researchers keep finding attacks that sound harder than they actually are.
Plenty to clean up. Here’s the short version.
## ⚡ Threat of the Week
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Bugzilla
CVE-2026-75874 firefox: thunderbird: Sandbox escape in the Remote Settings Client component
bugzilla·2026-08-18·CVSS 10.0
CVE-2026-75874 [CRITICAL] CVE-2026-75874 firefox: thunderbird: Sandbox escape in the Remote Settings Client component
CVE-2026-75874 firefox: thunderbird: Sandbox escape in the Remote Settings Client component
Sandbox escape in the Remote Settings Client component. This vulnerability was fixed in Firefox 154.
https://bugzilla.mozilla.org/show_bug.cgi?id=2039972https://www.mozilla.org/security/advisories/mfsa2026-74/https://www.mozilla.org/security/advisories/mfsa2026-78/https://www.mozilla.org/security/advisories/mfsa2026-83/https://www.mozilla.org/security/advisories/mfsa2026-84/https://www.mozilla.org/security/advisories/mfsa2026-85/https://www.mozilla.org/security/advisories/mfsa2026-87/https://www.mozilla.org/security/advisories/mfsa2026-88/
2026-08-18
Published