Vulnerability · Published Feb 26, 2021 · Assigned by mozilla
CVE-2021-23959
Medium 6.1
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 0.6% (higher than 47% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Severity (CVSS NVD)6.1Medium
Exploit odds (30 days)0.6%top 52.8% of all CVEs
Exploited in the wildNo reportsnot in CISA KEV
Attack toolingNoneno public tooling known
Official description
An XSS bug in internal error pages could have led to various spoofing attacks, including other error pages and the address bar. Note: This issue only affected Firefox for Android. Other operating systems are unaffected. This vulnerability affects Firefox < 85.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine:v3.20 | firefox | 85.0-r0 | ALPINE-CVE-2021-23959 |
| Alpine:v3.21 | firefox | 85.0-r0 | ALPINE-CVE-2021-23959 |
| Alpine:v3.22 | firefox | 85.0-r0 | ALPINE-CVE-2021-23959 |
| Alpine:v3.23 | firefox | 85.0-r0 | ALPINE-CVE-2021-23959 |
| Alpine:v3.21 | librewolf | 85.0-r0 | ALPINE-CVE-2021-23959 |
| Alpine:v3.22 | librewolf | 85.0-r0 | ALPINE-CVE-2021-23959 |
| Alpine:v3.23 | librewolf | 85.0-r0 | ALPINE-CVE-2021-23959 |
| Alpine:v3.24 | librewolf | 85.0-r0 | ALPINE-CVE-2021-23959 |
Affected products (as reported)
References
- https://www.mozilla.org/security/advisories/mfsa2021-03/ x_refsource_MISC
- https://bugzilla.mozilla.org/show_bug.cgi?id=1659035 x_refsource_MISC