Vulnerability · Published Feb 26, 2021 · Assigned by mozilla
CVE-2021-23958
Medium 6.5
In plain English
A medium-severity security flaw in Firefox from Mozilla. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.9% (higher than 59% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Severity (CVSS NVD)6.5Medium
Exploit odds (30 days)0.9%top 40.8% of all CVEs
Exploited in the wildNo reportsnot in CISA KEV
Attack toolingNoneno public tooling known
Official description
The browser could have been confused into transferring a screen sharing state into another tab, which would leak unintended information. This vulnerability affects Firefox < 85.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine:v3.20 | firefox | 85.0-r0 | ALPINE-CVE-2021-23958 |
| Alpine:v3.21 | firefox | 85.0-r0 | ALPINE-CVE-2021-23958 |
| Alpine:v3.22 | firefox | 85.0-r0 | ALPINE-CVE-2021-23958 |
| Alpine:v3.23 | firefox | 85.0-r0 | ALPINE-CVE-2021-23958 |
| Alpine:v3.21 | librewolf | 85.0-r0 | ALPINE-CVE-2021-23958 |
| Alpine:v3.22 | librewolf | 85.0-r0 | ALPINE-CVE-2021-23958 |
| Alpine:v3.23 | librewolf | 85.0-r0 | ALPINE-CVE-2021-23958 |
| Alpine:v3.24 | librewolf | 85.0-r0 | ALPINE-CVE-2021-23958 |
| Ubuntu:22.04:LTS | mozjs78 | no fix listed | UBUNTU-CVE-2021-23958 |
Affected products (as reported)
References
- https://www.mozilla.org/security/advisories/mfsa2021-03/ x_refsource_MISC
- https://bugzilla.mozilla.org/show_bug.cgi?id=1642747 x_refsource_MISC