CVE-2026-8958
published 2026-05-19CVE-2026-8958: Information disclosure, sandbox escape in the Security: Process Sandboxing component. This vulnerability was fixed in Firefox 151, Firefox ESR 140.11…
PriorityP346high8.6CVSS 3.1
AVNACLPRNUINSCCHINAN
EPSS
0.34%
26.6th percentile
Information disclosure, sandbox escape in the Security: Process Sandboxing component. This vulnerability was fixed in Firefox 151, Firefox ESR 140.11, Thunderbird 151, and Thunderbird 140.11.
Affected
10 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| mozilla | firefox | < Firefox 151 | Firefox 151 |
| mozilla | firefox | < 140.11.0 | 140.11.0 |
| mozilla | firefox | < 151.0.0 | 151.0.0 |
| mozilla | firefox | — | — |
| mozilla | firefox_esr | < Firefox ESR 140.11 | Firefox ESR 140.11 |
| mozilla | thunderbird | < Thunderbird 151 | Thunderbird 151 |
| mozilla | thunderbird | < Thunderbird 140.11 | Thunderbird 140.11 |
| mozilla | thunderbird | < 140.11 | 140.11 |
| mozilla | thunderbird | < 151.0.0 | 151.0.0 |
| rhel10 | firefox-flatpak | — | — |
CVSS provenance
nvdv3.18.6HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:N
vendor_redhat8.6HIGH
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Red Hat
firefox: Information disclosure, sandbox escape in the Security: Process Sandboxing component
vendor_redhat·2026-05-19·CVSS 8.6
CVE-2026-8958 [HIGH] CWE-403 firefox: Information disclosure, sandbox escape in the Security: Process Sandboxing component
firefox: Information disclosure, sandbox escape in the Security: Process Sandboxing component
A flaw was found in Firefox. The Mozilla Foundation's Security Advisory describes the following issue:
Information disclosure, sandbox escape in the Security: Process Sandboxing 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: firefox (Red Hat Enterprise Linux 6) - Out of support scope
Package: firefox (Red Hat Enterprise Linux 7) - Affected
Package: firefox (Red Hat Enterprise Linux 8) - Affected
Package: firefox (Red Hat Enterprise Linux 9) - Affected
Mozilla
Mozilla Foundation Security Advisory 2026-46: CVE-2026-8958
vendor_mozilla·CVSS 8.6
CVE-2026-8958 [HIGH] Mozilla Foundation Security Advisory 2026-46: CVE-2026-8958
Mozilla Foundation Security Advisory 2026-46
CVE: CVE-2026-8958
Product: Firefox
Impact: high
Fixed in: Firefox 151
Mozilla
Mozilla Foundation Security Advisory 2026-50: CVE-2026-8958
vendor_mozilla·CVSS 8.6
CVE-2026-8958 [HIGH] Mozilla Foundation Security Advisory 2026-50: CVE-2026-8958
Mozilla Foundation Security Advisory 2026-50
CVE: CVE-2026-8958
Product: Thunderbird
Impact: high
Fixed in: Thunderbird 151
Mozilla
Mozilla Foundation Security Advisory 2026-48: CVE-2026-8958
vendor_mozilla·CVSS 8.6
CVE-2026-8958 [HIGH] Mozilla Foundation Security Advisory 2026-48: CVE-2026-8958
Mozilla Foundation Security Advisory 2026-48
CVE: CVE-2026-8958
Product: Firefox ESR
Impact: high
Fixed in: Firefox ESR 140.11
Mozilla
Mozilla Foundation Security Advisory 2026-51: CVE-2026-8958
vendor_mozilla·CVSS 8.6
CVE-2026-8958 [HIGH] Mozilla Foundation Security Advisory 2026-51: CVE-2026-8958
Mozilla Foundation Security Advisory 2026-51
CVE: CVE-2026-8958
Product: Thunderbird
Impact: high
Fixed in: Thunderbird 140.11
GHSA
GHSA-gm4c-ph85-6chj: Information disclosure, sandbox escape in the Security: Process Sandboxing component
ghsa_unreviewed·2026-05-19
CVE-2026-8958 [HIGH] CWE-668 GHSA-gm4c-ph85-6chj: Information disclosure, sandbox escape in the Security: Process Sandboxing component
Information disclosure, sandbox escape in the Security: Process Sandboxing component. This vulnerability was fixed in Firefox 151 and Firefox ESR 140.11.
VulDB
Mozilla Firefox up to 150 Process Sandboxing sandbox
vuldb·2026-05-19·CVSS 8.6
CVE-2026-8958 [HIGH] Mozilla Firefox up to 150 Process Sandboxing sandbox
A vulnerability classified as critical has been found in Mozilla Firefox up to 150. The impacted element is an unknown function of the component Process Sandboxing. This manipulation causes sandbox issue.
This vulnerability is tracked as CVE-2026-8958. The attack is possible to be carried out remotely. No exploit exists.
It is recommended to upgrade the affected component.
No detection rules found.
No public exploits indexed.
2026-05-19
Published