Buffer overflow in Mozilla Firefox

CVE-2018-12393

A potential vulnerability was found in 32-bit builds where an integer overflow during the conversion of scripts to an internal UTF-16 representation could result in allocating a buffer too small for the conversion. This leads to a possible out-of-bounds write. *Note: 64-bit builds are not vulnerable to this issue.*. This vulnerability affects Firefox < 63, Firefox ESR < 60.3, and Thunderbird < 60.3.

Vulnerability class: Integer Overflow

EPSS: 0.039 (89.3th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2018-12393?
CVE-2018-12393 is a high-severity vulnerability in Mozilla Firefox, classified under Integer Overflow or Wraparound. CVSS score: 7.5/10. Published 2019-02-28.
How severe is CVE-2018-12393?
High severity. CVSS v3 base score is 7.5 out of 10.