Vulnerability in Mozilla Firefox
CVE-2021-23985
If an attacker is able to alter specific about:config values (for example malware running on the user's computer), the Devtools remote debugging feature could have been enabled in a way that was unnoticable to the user. This would have allowed a remote attacker (able to make a direct network connection to the victim) to monitor the user's browsing activity and (plaintext) network traffic. This was addressed by providing a visual cue when Devtools has an open network socket. This vulnerability affects Firefox < 87.
EPSS: 0.014 (69.6th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N.
Affected products
- Mozilla Firefox — versions unspecified
Public proof-of-concept exploits
References
- security@mozilla.org (x_refsource_MISC, Vendor Advisory)
- security@mozilla.org (Permissions Required, x_refsource_MISC, Issue Tracking, Vendor Advisory)
Frequently asked questions
- What is CVE-2021-23985?
- CVE-2021-23985 is a medium-severity vulnerability in Mozilla Firefox. CVSS score: 6.5/10. Published 2021-03-31.
- How severe is CVE-2021-23985?
- Medium severity. CVSS v3 base score is 6.5 out of 10.
- Is CVE-2021-23985 known to be exploited?
- 1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.