Memory Corruption in Firefox/Thunderbird 151 Enables RCE
CVE-2026-12326 Published on June 16, 2026
Memory safety bugs fixed in Firefox 152 and Thunderbird 152
Memory safety bugs present in Firefox 151 and Thunderbird 151. 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 152 and Thunderbird 152.
Vulnerability Analysis
CVE-2026-12326 is exploitable with network access, and does not require authorization privileges or user interaction. This vulnerability is consided to have a high level of attack complexity. The potential impact of an exploit of this vulnerability is considered to be very high.
Weakness Type
What is a Buffer Overflow Vulnerability?
The software performs operations on a memory buffer, but it can read from or write to a memory location that is outside of the intended boundary of the buffer.
CVE-2026-12326 has been classified to as a Buffer Overflow vulnerability or weakness.
Products Associated with CVE-2026-12326
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Affected Versions
Mozilla Firefox:- Version 152, <= * is unaffected.
- Version 152, <= * is unaffected.
Exploit Probability
EPSS (Exploit Prediction Scoring System) scores estimate the probability that a vulnerability will be exploited in the wild within the next 30 days. The percentile shows you how this score compares to all other vulnerabilities.