CVE-2021-23977

Description

Firefox for Android suffered from a time-of-check-time-of-use vulnerability that allowed a malicious application to read sensitive data from application directories. Note: This issue is only affected Firefox for Android. Other operating systems are unaffected. This vulnerability affects Firefox < 86.

Category

5.3
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.28%
Vendor Advisory gentoo.org Vendor Advisory mozilla.org Vendor Advisory mozilla.org
Affected: Mozilla Firefox
Published at:
Updated at:

References

Link Tags
https://www.mozilla.org/security/advisories/mfsa2021-07/ release notes vendor advisory
https://bugzilla.mozilla.org/show_bug.cgi?id=1684761 issue tracking permissions required vendor advisory
https://security.gentoo.org/glsa/202104-10 third party advisory vendor advisory

Frequently Asked Questions

What is the severity of CVE-2021-23977?
CVE-2021-23977 has been scored as a medium severity vulnerability.
How to fix CVE-2021-23977?
To fix CVE-2021-23977, 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-2021-23977 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-23977 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-23977?
CVE-2021-23977 affects Mozilla Firefox.
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