VULNERABILITY INTELLIGENCE
CVE-2021-43542
CVSS score6.5 MEDIUM
EPSS probability1.83%
CISA KEVNot currently listed
Published2021-12-08
Last modified2026-06-17
CVSS vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N
Description
Using XMLHttpRequest, an attacker could have identified installed applications by probing error messages for loading external protocols. This vulnerability affects Thunderbird < 91.4.0, Firefox ESR < 91.4.0, and Firefox < 95.
Weakness classification
- nvd@nist.gov: CWE-209
Primary references
- security@mozilla.org — Issue Tracking, Permissions Required, Vendor Advisory
- security@mozilla.org — Mailing List, Third Party Advisory
- security@mozilla.org — Mailing List, Third Party Advisory
- security@mozilla.org — Third Party Advisory
- security@mozilla.org — Third Party Advisory
- security@mozilla.org — Third Party Advisory
- security@mozilla.org — Third Party Advisory
- security@mozilla.org — Vendor Advisory
- security@mozilla.org — Vendor Advisory
- security@mozilla.org — Vendor Advisory
- af854a3a-2127-422b-91ae-364da2661108 — Issue Tracking, Permissions Required, Vendor Advisory
- af854a3a-2127-422b-91ae-364da2661108 — Mailing List, Third Party Advisory