CVE-2021-29953

Description

A malicious webpage could have forced a Firefox for Android user into executing attacker-controlled JavaScript in the context of another domain, resulting in a Universal Cross-Site Scripting vulnerability. *Note: This issue only affected Firefox for Android. Other operating systems are unaffected. Further details are being temporarily withheld to allow users an opportunity to update.*. This vulnerability affects Firefox < 88.0.1 and Firefox for Android < 88.1.3.

Category

6.1
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.69% Top 30%
Vendor Advisory mozilla.org Vendor Advisory mozilla.org
Affected: Mozilla Firefox
Affected: Mozilla Firefox for Android
Published at:
Updated at:

References

Link Tags
https://www.mozilla.org/security/advisories/mfsa2021-20/ release notes vendor advisory
https://bugzilla.mozilla.org/show_bug.cgi?id=1701684 permissions required vendor advisory

Frequently Asked Questions

What is the severity of CVE-2021-29953?
CVE-2021-29953 has been scored as a medium severity vulnerability.
How to fix CVE-2021-29953?
To fix CVE-2021-29953, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-29953 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-29953 is being actively exploited. According to its EPSS score, there is a ~1% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-29953?
CVE-2021-29953 affects Mozilla Firefox, Mozilla Firefox for Android.
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