Vulnerability Database

310,057

Total vulnerabilities in the database

CVE-2021-23995

When Responsive Design Mode was enabled, it used references to objects that were previously freed. We presume that with enough effort this could have been exploited to run arbitrary code. This vulnerability affects Firefox ESR < 78.10, Thunderbird < 78.10, and Firefox < 88.

  • Published: Jun 24, 2021
  • Updated: Nov 16, 2025
  • CVE: CVE-2021-23995
  • Severity: High
  • Exploit:

CVSS v3:

  • Severity: High
  • Score: 8.8
  • AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

CVSS v2:

  • Severity: Medium
  • Score: 5.1
  • AV:N/AC:H/Au:N/C:P/I:P/A:P

CWEs:

Software From Fixed in
mozilla / thunderbird - 78.10
mozilla / firefox - 88.0
mozilla / firefox_esr - 78.10