CVE-2021-23985: mozilla firefox
Vulnerability summary
CVE-2021-23985 is a medium (CVSS 6.5) vulnerability in mozilla firefox. EPSS estimates a 1.51% chance of exploitation in the next 30 days, higher than 73.9% of scored vulnerabilities.
Advisory lineage
Upstream 0 · Downstream 3 · Related 3Timeline
- 31-03-2021PublishedVulnerability first disclosed.
- 03-08-2024Last modifiedVulnerability information updated.
Description
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.
CVSS metrics
3 scores · 2 sources · 2 versions- OSV · UbuntuEcosystem advisory · calculated6.5MediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N
EPSS trend
Probability
1.51%
Chance of exploitation in the next 30 days
Percentile
74%
Versus all other CVEs
30-day change
0.00 pp
From 1.51% on 19-09-2026
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeNo weakness data has been published for this record.
Affected systems
Ubuntu5 products
- firefox< 87.0+build3-0ubuntu0.16.04.2 | < 87.0+build3-0ubuntu0.18.04.2 | < 87.0+build3-0ubuntu0.20.04.2
- mozjs38All versions (No fix recorded)
- mozjs52All versions (No fix recorded)
- mozjs68All versions (No fix recorded)
- mozjs78All versions (No fix recorded)
Mozilla1 product
- firefox≥ unspecified, < 87 | < 87.0
2 vendors · 6 products
References
6 links- bugzilla.mozilla.org/show_bug.cgi?id=1659129X Refsource MISCIssue TrackingPermissions RequiredVendor Advisory