CVE-2026-2776

Description

Sandbox escape due to incorrect boundary conditions in the Telemetry component in External Software. This vulnerability was fixed in Firefox 148, Firefox ESR 115.33, Firefox ESR 140.8, Thunderbird 148, and Thunderbird 140.8.

References

• https://www.cnvd.org.cn/flaw/show/CNVD-2026-20782
• http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2026-2776
• https://bugzilla.mozilla.org/show_bug.cgi?id=2015266
• https://euvd.enisa.europa.eu/vulnerability/EUVD-2026-8498
• https://www.mozilla.org/security/advisories/mfsa2026-13/
• https://www.mozilla.org/security/advisories/mfsa2026-14/
• https://www.mozilla.org/security/advisories/mfsa2026-15/
• https://www.mozilla.org/security/advisories/mfsa2026-16/
• https://www.mozilla.org/security/advisories/mfsa2026-17/