CVE-2026-6764
MediumCVSS 6.5Exploitation Probability (EPSS)
Low risk14th percentile - higher than 14% of all known CVEs
Summary
Incorrect boundary conditions exist in the DOM: Device Interfaces component of Firefox and Thunderbird. The issue was fixed in Firefox 150, Firefox ESR 140.10, Thunderbird 150, and Thunderbird 140.10.
Risk Assessment
The flaw may enable memory corruption and potential code execution when processing crafted pages or content. Users of vulnerable browser and mail client versions are exposed.
Recommendation
Update Firefox, Firefox ESR, and Thunderbird to the listed fixed versions. Prioritize updating the ESR channel in enterprise environments.
Other vulnerabilities in Firefox / Thunderbird
See all- CVE-2026-16408Critical
Integer overflow in the Audio/Video: Playback component in Firefox and Thunderbird. Fixed in versions 153.
- CVE-2026-16395Critical
Integer overflow in the Audio/Video component in Firefox and Thunderbird. Fixed in versions 153.
- CVE-2026-6770Medium
A security issue exists in the Storage: IndexedDB component of the Firefox browser and the Thunderbird mail client. The vulnerability was fixed in Firefox 150, Firefox ESR 140.10, Thunderbird 150, and Thunderbird 140.10.
- CVE-2026-4729Critical
Memory safety bugs were found in Firefox 148 and Thunderbird 148. Some of these bugs showed evidence of memory corruption, which could potentially allow arbitrary code execution. The vulnerabilities were fixed in Firefox 149 and Thunderbird 149.
- CVE-2026-4720Critical
Memory safety bugs were found in Firefox ESR 140.8, Thunderbird ESR 140.8, Firefox 148 and Thunderbird 148. Some of these bugs showed evidence of memory corruption and could potentially be exploited to run arbitrary code with enough effort.
- CVE-2026-2807Critical
Memory safety bugs were found in Firefox 147 and Thunderbird 147. Some of these bugs showed evidence of memory corruption and could potentially be exploited to run arbitrary code. The vulnerability was fixed in Firefox 148 and Thunderbird 148.
- CVE-2026-2792Critical
Memory safety bugs were found in Firefox ESR 140.7, Firefox 147, Thunderbird ESR 140.7, and Thunderbird 147. Some of these bugs showed evidence of memory corruption and could potentially be exploited to run arbitrary code with enough effort.
- CVE-2026-118008High
Privilege escalation vulnerability in the DOM: Navigation component. It was fixed in Firefox 159 and Thunderbird 159.
- CVE-2026-117991Low risk· EPSS 8%
The vulnerability stems from incorrect boundary conditions in the Layout: Text and Fonts component of Firefox and Thunderbird. It was fixed in Firefox 159, Firefox ESR 153.6, Thunderbird 159, and Thunderbird 153.6.
- CVE-2026-117990Low risk· EPSS 8%
The vulnerability allows a sandbox escape due to incorrect boundary conditions in the Graphics: WebRender component. It was fixed in Firefox 159, Firefox ESR 153.6, Thunderbird 159, and Thunderbird 153.6.
Original NVD description (English source)
Incorrect boundary conditions in the DOM: Device Interfaces component. This vulnerability was fixed in Firefox 150, Firefox ESR 140.10, Thunderbird 150, and Thunderbird 140.10.
Vulnerability data from NVD (NIST) · CISA KEV · EPSS

