Vulnerability Database

310,057

Total vulnerabilities in the database

CVE-2021-23999

If a Blob URL was loaded through some unusual user interaction, it could have been loaded by the System Principal and granted additional privileges that should not be granted to web content. This vulnerability affects Firefox ESR < 78.10, Thunderbird < 78.10, and Firefox < 88.

  • Published: Jun 24, 2021
  • Updated: Nov 16, 2025
  • CVE: CVE-2021-23999
  • 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: 6.8
  • AV:N/AC:M/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