CVE intelligence and bounded remediation

CVE-2018-12393 — Mozilla Firefox security vulnerability

High CVSS 7.5

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.

Severity
High
CVSS
7.5 (3.0)
Published
2019-02-28
CISA KEV
Not currently listed
Ecosystem
browser
Weaknesses
CWE-190, CWE-787

Affected products

  • mozilla / firefox
  • mozilla / firefox_esr
  • mozilla / thunderbird
  • debian / debian_linux / 8.0
  • debian / debian_linux / 9.0
  • canonical / ubuntu_linux / 14.04

Showing 6 representative product identities from 18 source matches. Confirm exact affected versions with the linked vendor and NVD evidence.

Matched remediation archetype

Buffer bounds, memory safety, and memory corruption

This catalog composition supplies bounded fallback guidance. Explicitly reviewed curated workflows load with the complete record below.

Check exposure

  • Identify affected native-code versions, build flags, architectures, parsers, codecs, drivers, and input paths in all shipped artifacts.
  • Determine whether untrusted data reaches the affected routine and the process privilege, sandbox, and network exposure.
  • Confirm statically linked, vendored, firmware, and platform-provided copies, not only package-manager records.

Remediate safely

  • Apply the maintained upstream correction or replace the affected component, then rebuild every dependent artifact from clean inputs.
  • Adopt bounds-checked interfaces, validated sizes and integer conversions, clear ownership, and memory-safe components where practical.
  • Enable supported compiler and runtime hardening and add sanitized tests and fuzz regression seeds derived from non-weaponized fixtures.

Authoritative sources

Complete CVE record and remediation plan

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