CVE-2026-14899
7.5 · HIGHOverview
CVE-2026-14899 is a high-severity vulnerability affecting mozilla thunderbird. It was published on July 22, 2026 and has a CVSS 3.1 base score of 7.5 (HIGH).
This vulnerability has a CVSS 3.1 base score of 7.5, rated HIGH. It can be exploited remotely over the network. No authentication or special privileges are required for exploitation.
Technical Description
The code to parse MIME headers for display when forwarding a message (if the setting to view all headers was enabled) had an off-by-one error, allowing a single byte to be read from the memory after the buffer for the headers, and potentially crashing Thunderbird. This vulnerability was fixed in Thunderbird 153 and Thunderbird 140.13.
Remediation
Check the references section for vendor advisories and patches from mozilla. Update thunderbird to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
Affected Products
| Vendor | Product | Versions | Status |
|---|---|---|---|
| mozilla | thunderbird | >= 0, < 140.13.0 | Affected |
Frequently Asked Questions
What is CVE-2026-14899?
CVE-2026-14899 is a high-severity vulnerability affecting mozilla thunderbird. It was published on July 22, 2026 and has a CVSS 3.1 base score of 7.5 (HIGH).
How severe is CVE-2026-14899?
This vulnerability has a CVSS 3.1 base score of 7.5, rated HIGH. It can be exploited remotely over the network. No authentication or special privileges are required for exploitation.
How do I fix or remediate CVE-2026-14899?
Check the references section for vendor advisories and patches from mozilla. Update thunderbird to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
How can CyberStrike help with CVE-2026-14899?
CyberStrike's AI-powered security agents can automatically detect CVE-2026-14899 across your infrastructure using autonomous pentesting, DAST scanning, and HackBrowser. The platform continuously monitors for known vulnerabilities and provides actionable remediation guidance prioritized by real-world exploitability.
How CyberStrike Helps
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