CVSS 3.1
8.8 highCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:HCVE-2026-124951 Privilege escalation in the Nimbus Desktop Client component
High (8.8) in mozilla. EPSS 0.2% estimated probability of exploitation activity in the next 30 days.
On this page
Privilege escalation in the Nimbus Desktop Client component. This vulnerability was fixed in Firefox 160, Firefox ESR 153.7, Thunderbird 160, and Thunderbird 153.7.
Severity
- EPSS
- 0.2% estimated probability of exploitation activity in the next 30 days; 7th percentile. Scored 2026-11-13. A forecast for this CVE across the internet, not for your own systems.
- CISA's assessment (SSVC)
- Exploitation: none · Automatable: no · Technical impact: total, assessed 2026-11-13. From CISA's Vulnrichment in the CVE List: whether it is exploited, whether exploiting it can be automated, and how much control it gives.
- CWE
- CWE-269 Improper Privilege Management
- OWASP Top 10
- A06:2025 Insecure Design
- Published
- Modified
- Assigned by
- mozilla (CNA)
- NVD analysis
- Deferred: the NVD does not plan to analyze it
- Record from
- the NVD, synced
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Affected
Versions
From the CNA's record in the CVE List.
Fixed in
| Product | Release line | Fixed in |
|---|---|---|
| Mozilla Firefox | 153 | 153.7 |
| Mozilla Firefox | later releases | 160 |
| Mozilla Thunderbird | 153 | 153.7 |
| Mozilla Thunderbird | later releases | 160 |
Fix and patched versions
- Mozilla Firefox: fixed in 153.7
- Mozilla Firefox: fixed in 160
- Mozilla Thunderbird: fixed in 153.7
- Mozilla Thunderbird: fixed in 160
- Debian, Red Hat, SUSE, openSUSE, AlmaLinux, Rocky Linux: fixed package versions per release
Linux distributions
| Distribution | Release | Package | Fixed in | Advisory |
|---|---|---|---|---|
| Debian | 12 | firefox-esr | 153.7.0esr-1~deb12u1 | DEBIAN-CVE-2026-124951 |
| Debian | 12 | thunderbird | 1:153.7.0esr-1~deb12u1 | DEBIAN-CVE-2026-124951 |
| Debian | 13 | firefox-esr | 153.7.0esr-1~deb13u1 | DEBIAN-CVE-2026-124951 |
| Debian | 13 | thunderbird | 1:153.7.0esr-1~deb13u1 | DEBIAN-CVE-2026-124951 |
| Debian | 14 | firefox-esr, thunderbird | no fix listed | DEBIAN-CVE-2026-124951 |
| Ubuntu | 18.04:LTS | mozjs38, mozjs52 | no fix listed | UBUNTU-CVE-2026-124951 |
| Ubuntu | 20.04:LTS | mozjs52, mozjs68 | no fix listed | UBUNTU-CVE-2026-124951 |
| Ubuntu | 22.04:LTS | mozjs78, mozjs91, mozjs102 and 1 more | no fix listed | UBUNTU-CVE-2026-124951 |
| Ubuntu | 24.04:LTS | mozjs102, mozjs115 | no fix listed | UBUNTU-CVE-2026-124951 |
| Red Hat | enterprise_linux:8::appstream | firefox, firefox-debuginfo, firefox-debugsource | 0:153.7.0-1.el8_10 | RHSA-2026:99112 |
| Red Hat | enterprise_linux:9::appstream | firefox, firefox-x11, firefox-debuginfo and 1 more | 0:153.7.0-1.el9_9 | RHSA-2026:99111 |
| Red Hat | enterprise_linux:10.3 | firefox, firefox-debuginfo, firefox-debugsource | 0:153.7.0-1.el10_3 | RHSA-2026:99572 |
| Red Hat | enterprise_linux_eus:10.2 | firefox, firefox-debuginfo, firefox-debugsource | 0:153.7.0-1.el10_2 | RHSA-2026:99571 |
| Red Hat | rhel_eus:9.8::appstream | firefox, firefox-x11, firefox-debuginfo and 1 more | 0:153.7.0-1.el9_8 | RHSA-2026:99110 |
| SUSE | Linux Enterprise High Performance Computing 15 SP4-ESPOS, Linux Enterprise High Performance Computing 15 SP4-LTSS, Linux Enterprise High Performance Computing 15 SP5-ESPOS and 8 more | MozillaFirefox | 153.7.0-150400.157.22.1 | SUSE-SU-2026:5229-1 |
| SUSE | Linux Enterprise Server 12 SP5-LTSS, Linux Enterprise Server LTSS Extended Security 12 SP5 | MozillaFirefox | 153.7.0-118.22.1 | SUSE-SU-2026:5174-1 |
| openSUSE | Tumbleweed | firefox-esr | 153.7.0-1.1 | openSUSE-SU-2026:12527-1 |
| AlmaLinux | 8 | firefox | 153.7.0-1.el8_10 | ALSA-2026:99112 |
| Rocky Linux | 8 | firefox, firefox-debuginfo, firefox-debugsource | 0:153.7.0-1.el8_10 | RLSA-2026:99112 |
| Rocky Linux | 9 | firefox, firefox-x11, firefox-debuginfo and 1 more | 0:153.7.0-1.el9_9 | RLSA-2026:99111 |
From the distributions' data via OSV.dev: the Debian Security Tracker; Ubuntu Security Notices © Canonical Ltd., CC BY-SA 4.0; Red Hat Security Data © Red Hat, Inc., CC BY 4.0; SUSE security data, CC BY 4.0; AlmaLinux's OSV database, MIT; Rocky Linux's errata, BSD-3-Clause. Modified: reformatted and linked to CVE records. Credits. On the distributions' own pages: Debian · Ubuntu · Red Hat · SUSE · openSUSE.
Red Hat
Red Hat rates this Low.
Red Hat Product Security rates the severity of this flaw as determined by the Mozilla Foundation Security Advisory.
| Product | Package | State | Advisory |
|---|---|---|---|
| Red Hat Enterprise Linux 10 | firefox-0:153.7.0-1.el10_3 | Fixed 2026-11-12 | RHSA-2026:99572 |
| Red Hat Enterprise Linux 10.2 Extended Update Support | firefox-0:153.7.0-1.el10_2 | Fixed 2026-11-12 | RHSA-2026:99571 |
| Red Hat Enterprise Linux 8 | firefox-0:153.7.0-1.el8_10 | Fixed 2026-11-11 | RHSA-2026:99112 |
| Red Hat Enterprise Linux 9 | firefox-0:153.7.0-1.el9_9 | Fixed 2026-11-11 | RHSA-2026:99111 |
| Red Hat Enterprise Linux 9.8 Extended Update Support | firefox-0:153.7.0-1.el9_8 | Fixed 2026-11-11 | RHSA-2026:99110 |
| Red Hat Enterprise Linux 10 | rhel10/firefox-flatpak | Affected | |
| Red Hat Enterprise Linux 10 | rhel10/thunderbird-flatpak | Affected | |
| Red Hat Enterprise Linux 10 | thunderbird | Affected | |
| Red Hat Enterprise Linux 6 | firefox | Out of support scope | |
| Red Hat Enterprise Linux 6 | thunderbird | Out of support scope | |
| Red Hat Enterprise Linux 7 | firefox | Affected | |
| Red Hat Enterprise Linux 7 | thunderbird | Out of support scope | |
| Red Hat Enterprise Linux 8 | thunderbird | Affected | |
| Red Hat Enterprise Linux 9 | thunderbird | Affected |
Contains Red Hat Security Data © Red Hat, Inc., licensed under CC BY 4.0. Source: https://access.redhat.com/security/data. Modified: reformatted. Red Hat's page for CVE-2026-124951.
Attack patterns (CAPEC)
- CAPEC-58 Restful Privilege Elevation Likelihood: High · Severity: High
- CAPEC-122 Privilege Abuse Likelihood: High · Severity: Medium
- CAPEC-233 Privilege Escalation
The attack patterns MITRE's CAPEC relates to this record's weaknesses, as MITRE names them. Credits.
History
- The NVD deferred its analysis
- Scored 8.8 high
Changes since this site first stored the record. The same for every record: /api/public/changes.