CVE-2026-7323: mozilla firefox

Vulnerability summary

CVE-2026-7323 is a high (CVSS 7.3) vulnerability in mozilla firefox. EPSS estimates a 0.46% chance of exploitation in the next 30 days, higher than 38.6% of scored vulnerabilities.

Timeline

1. 28-04-2026
   PublishedVulnerability first disclosed.
2. 15-07-2026
   Last modifiedVulnerability information updated.

Description

Memory safety bugs present in Thunderbird ESR 140.10.0 and Thunderbird 150.0.0. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code. This vulnerability was fixed in Firefox 150.0.1, Firefox ESR 140.10.1, Thunderbird 150.0.1, and Thunderbird 140.10.1.

• CWE-119Improper Restriction of Operations within the Bounds of a Memory BufferThe product performs operations on a memory buffer, but it reads from or writes to a memory location outside the buffer's intended boundary. This may result in read or write operations on unexpected memory locations that could be linked to other variables, data structures, or internal program data.
• CWE-787Out-of-bounds WriteThe product writes data past the end, or before the beginning, of the intended buffer.