VulnSea

Mozilla has 722 CVEs on record between 2016 and 2026. Disclosure cadence is accelerating: 438 in the last 90 days against 62 in the 90 before. The busiest recent month was October 2026 with 265. The median CVSS is 8.1 (high), with 141 rated critical. 0% have been exploited in the wild, in line with the corpus average. The dominant weakness classes are CWE-416 (108) and CWE-119 (56). Most affected products: Firefox (665), firefox_mobile (30), Thunderbird (19).

CVEs per month

Last 12 months, by publish date

120102030405060708091011
Exploited share
0% vs 1% corpus
Median CVSS
8.1
Publish → KEV
—(1)
Last 90 days
438 prev 62

Products

  • Firefox 665
  • firefox_mobile 30
  • Thunderbird 19
  • Firefox for iOS 4
  • firefox_focus 2
  • Node-convict 1
722
Total CVEs
141
Critical
3
CISA KEV
3
Exploited

Mozilla vulnerabilities

CVEs affecting Mozilla, newest first. Open any entry for full detail, references, and exploit status.

722 CVEsRSS

CVE-2026-12309Medium· 6.5
4mo ago

Memory safety bug fixed in Thunderbird 152

Memory safety bug fixed in Thunderbird 152. This vulnerability was fixed in Firefox 152, Firefox ESR 140.12, Thunderbird 152, and Thunderbird 140.12.

▾ SunlitMozilla · FirefoxEPSS 0.24%via CVEORG
CVE-2026-12308Medium· 5.3
4mo ago

Memory safety bug fixed in Thunderbird 152

Memory safety bug fixed in Thunderbird 152. This vulnerability was fixed in Firefox 152, Firefox ESR 140.12, Thunderbird 152, and Thunderbird 140.12.

▾ SunlitMozilla · FirefoxEPSS 0.26%via CVEORG
CVE-2026-12314High· 7.5
4mo ago

Memory safety bug fixed in Thunderbird 152

Memory safety bug fixed in Thunderbird 152. This vulnerability was fixed in Firefox 152, Firefox ESR 140.12, Thunderbird 152, and Thunderbird 140.12.

▾ TwilightMozilla · FirefoxEPSS 0.25%via CVEORG
CVE-2026-12312High· 7.5
4mo ago

Memory safety bug fixed in Thunderbird 152

Memory safety bug fixed in Thunderbird 152. This vulnerability was fixed in Firefox 152, Firefox ESR 140.12, Thunderbird 152, and Thunderbird 140.12.

▾ TwilightMozilla · FirefoxEPSS 0.25%via CVEORG
CVE-2026-12310High· 7.5
4mo ago

Memory safety bug fixed in Thunderbird 152

Memory safety bug fixed in Thunderbird 152. This vulnerability was fixed in Firefox 152, Firefox ESR 140.12, Thunderbird 152, and Thunderbird 140.12.

▾ TwilightMozilla · FirefoxEPSS 0.25%via CVEORG
CVE-2026-12317High· 7.5
4mo ago

Memory safety bug fixed in Thunderbird 152

Memory safety bug fixed in Thunderbird 152. This vulnerability was fixed in Firefox 152 and Thunderbird 152.

▾ TwilightMozilla · FirefoxEPSS 0.29%via CVEORG
CVE-2026-12329Medium· 5.3
4mo ago

Memory safety bug fixed in Thunderbird ESR 140.12

Memory safety bug fixed in Thunderbird ESR 140.12. This vulnerability was fixed in Firefox ESR 140.12 and Thunderbird 140.12.

▾ Sunlitmozilla · firefoxEPSS 0.31%via NVD
CVE-2026-12328High· 8.1
4mo ago

Memory safety bugs present in Firefox ESR 115.36, Firefox ESR 140.11, Thunderbird ESR 140.11, Firefox 151 and Thunderbird 151

Memory safety bugs present in Firefox ESR 115.36, Firefox ESR 140.11, Thunderbird ESR 140.11, Firefox 151 and Thunderbird 151. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these c…

▾ Twilightmozilla · firefoxEPSS 0.48%via NVD
CVE-2026-12299Medium· 5.4
4mo ago

JIT miscompilation in the DOM: Core & HTML component

JIT miscompilation in the DOM: Core & HTML component. This vulnerability was fixed in Firefox 152, Firefox ESR 140.12, Firefox ESR 115.37, Thunderbird 152, and Thunderbird 140.12.

▾ Sunlitmozilla · firefoxEPSS 0.31%via NVD
CVE-2026-12298Medium· 5.4
4mo ago

Memory safety bug fixed in Firefox 152

Memory safety bug fixed in Firefox 152. This vulnerability was fixed in Firefox 152, Firefox ESR 140.12, Thunderbird 152, and Thunderbird 140.12.

▾ Sunlitmozilla · firefoxEPSS 0.31%via NVD
CVE-2026-12297Critical· 9.6
4mo ago

Sandbox escape due to incorrect boundary conditions in the Networking component

Sandbox escape due to incorrect boundary conditions in the Networking component. This vulnerability was fixed in Firefox 152, Firefox ESR 140.12, Firefox ESR 115.37, Thunderbird 152, and Thunderbird 140.12.

▾ Midnightmozilla · firefoxEPSS 0.39%via NVD
CVE-2026-12296Critical· 9.6
4mo ago

Sandbox escape in the Security: Process Sandboxing component

Sandbox escape in the Security: Process Sandboxing component. This vulnerability was fixed in Firefox 152, Firefox ESR 140.12, Thunderbird 152, and Thunderbird 140.12.

▾ Midnightmozilla · firefoxEPSS 0.39%via NVD
CVE-2026-12295Critical· 9.6PoC
4mo ago

Sandbox escape in the DOM: Navigation component

Sandbox escape in the DOM: Navigation component. This vulnerability was fixed in Firefox 152, Firefox ESR 140.12, Firefox ESR 115.37, Thunderbird 152, and Thunderbird 140.12.

▾ Abyssalmozilla · firefoxEPSS 0.39%via NVD
CVE-2026-12294Critical· 9.6
4mo ago

Sandbox escape in the DOM: Workers component

Sandbox escape in the DOM: Workers component. This vulnerability was fixed in Firefox 152, Firefox ESR 140.12, Firefox ESR 115.37, Thunderbird 152, and Thunderbird 140.12.

▾ Midnightmozilla · firefoxEPSS 0.36%via NVD
CVE-2026-12292High· 8.1
4mo ago

Incorrect boundary conditions in the Web Audio component

Incorrect boundary conditions in the Web Audio component. This vulnerability was fixed in Firefox 152, Firefox ESR 140.12, Thunderbird 152, and Thunderbird 140.12.

▾ Twilightmozilla · firefoxEPSS 0.49%via NVD
CVE-2026-12291High· 8.8
4mo ago

Use-after-free in the Networking: HTTP component

Use-after-free in the Networking: HTTP component. This vulnerability was fixed in Firefox 152, Firefox ESR 140.12, Firefox ESR 115.37, Thunderbird 152, and Thunderbird 140.12.

▾ Twilightmozilla · firefoxEPSS 0.38%via NVD
CVE-2026-12290High· 8.1
4mo ago

Memory safety bug fixed in Firefox 152

Memory safety bug fixed in Firefox 152. This vulnerability was fixed in Firefox 152, Firefox ESR 140.12, Firefox ESR 115.37, Thunderbird 152, and Thunderbird 140.12.

▾ Twilightmozilla · firefoxEPSS 0.40%via NVD
CVE-2026-12289High· 8.8
4mo ago

Privilege escalation in the Graphics: WebRender component

Privilege escalation in the Graphics: WebRender component. This vulnerability was fixed in Firefox 152, Firefox ESR 140.12, Firefox ESR 115.37, Thunderbird 152, and Thunderbird 140.12.

▾ Twilightmozilla · firefoxEPSS 0.40%via NVD
CVE-2026-8960High· 7.5
5mo ago

Spoofing issue in WebExtensions

Spoofing issue in WebExtensions. This vulnerability was fixed in Firefox 151 and Thunderbird 151.

▾ Twilightmozilla · firefoxEPSS 0.38%via NVD
CVE-2026-8959Critical· 9.6
5mo ago

Sandbox escape due to incorrect boundary conditions in the Widget: Win32 component

Sandbox escape due to incorrect boundary conditions in the Widget: Win32 component. This vulnerability was fixed in Firefox 151, Firefox ESR 140.11, Thunderbird 151, and Thunderbird 140.11.

▾ Midnightmozilla · firefoxEPSS 0.42%via NVD
CVE-2026-8958High· 8.6
5mo ago

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, Firefox ESR 140.11, Thunderbird 151, and Thunderbird 140.11.

▾ Twilightmozilla · firefoxEPSS 0.34%via NVD
CVE-2026-8957High· 8.8
5mo ago

Privilege escalation in the Enterprise Policies component

Privilege escalation in the Enterprise Policies component. This vulnerability was fixed in Firefox 151, Firefox ESR 140.11, Thunderbird 151, and Thunderbird 140.11.

▾ Twilightmozilla · firefoxEPSS 0.39%via NVD
CVE-2026-8956Critical· 9.8
5mo ago

Integer overflow in the Networking: JAR component

Integer overflow in the Networking: JAR component. This vulnerability was fixed in Firefox 151, Firefox ESR 140.11, Thunderbird 151, and Thunderbird 140.11.

▾ Midnightmozilla · firefoxEPSS 0.60%via NVD
CVE-2026-8955High· 8.8
5mo ago

Privilege escalation in the DOM: Workers component

Privilege escalation in the DOM: Workers component. This vulnerability was fixed in Firefox 151, Firefox ESR 140.11, Thunderbird 151, and Thunderbird 140.11.

▾ Twilightmozilla · firefoxEPSS 0.39%via NVD
CVE-2026-8954High· 7.5
5mo ago

Incorrect boundary conditions, integer overflow in the Audio/Video component

Incorrect boundary conditions, integer overflow in the Audio/Video component. This vulnerability was fixed in Firefox 151, Firefox ESR 140.11, Thunderbird 151, and Thunderbird 140.11.

▾ Twilightmozilla · firefoxEPSS 0.43%via NVD
CVE-2026-8953Critical· 9.6
5mo ago

Sandbox escape due to use-after-free in the Disability Access APIs component

Sandbox escape due to use-after-free in the Disability Access APIs component. This vulnerability was fixed in Firefox 151, Firefox ESR 115.36, Firefox ESR 140.11, Thunderbird 151, and Thunderbird 140.11.

▾ Midnightmozilla · firefoxEPSS 0.53%via NVD
CVE-2026-8952High· 8.8
5mo ago

Privilege escalation in the Application Update component

Privilege escalation in the Application Update component. This vulnerability was fixed in Firefox 151 and Thunderbird 151.

▾ Twilightmozilla · firefoxEPSS 0.37%via NVD
CVE-2026-8951Medium· 6.5
5mo ago

Spoofing issue in the Toolbar component in Firefox for Android

Spoofing issue in the Toolbar component in Firefox for Android. This vulnerability was fixed in Firefox 151.

▾ Sunlitmozilla · firefoxEPSS 0.25%via NVD
CVE-2026-8950Critical· 9.3
5mo ago

Same-origin policy bypass in the Networking: HTTP component

Same-origin policy bypass in the Networking: HTTP component. This vulnerability was fixed in Firefox 151, Firefox ESR 140.11, Thunderbird 151, and Thunderbird 140.11.

▾ Midnightmozilla · firefoxEPSS 0.19%via NVD
CVE-2026-8949High· 7.5
5mo ago

Integer overflow in the Widget: Win32 component

Integer overflow in the Widget: Win32 component. This vulnerability was fixed in Firefox 151, Firefox ESR 140.11, Thunderbird 151, and Thunderbird 140.11.

▾ Twilightmozilla · firefoxEPSS 0.58%via NVD
Mozilla vulnerabilities (CVEs) — page 16 · VulnSea