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Status published
Medium
CVE-2021-23977
Firefox for Android suffered from a time-of-check-time-of-use vulnerability that allowed...
Vulnerability 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.
Impact Analysis
Refer to official advisory for detailed impact metrics.
Remediation
Ensure systems are updated to the latest vendor-supplied patch levels.
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Credits & Attribution
No credits recorded in the NVD database.
References
More from Mozilla
View All →CVE-2025-9187
Memory safety bugs fixed in Firefox 142 and Thunderbird 142
Unknown
0
CVE-2025-9186
Spoofing issue in the Address Bar component of Firefox Focus for Android
Unknown
0
CVE-2025-9185
Memory safety bugs fixed in Firefox ESR 115.27, Firefox ESR 128.14, Thunderbird ESR 128.14, Firefox ESR 140.2, Thunderbird ESR 140.2, Firefox 142 and Thunderbird 142
Unknown
0
CVE-2025-9184
Memory safety bugs fixed in Firefox ESR 140.2, Thunderbird ESR 140.2, Firefox 142 and Thunderbird 142
Unknown
0
CVE-2025-9183
Spoofing issue in the Address Bar component
Unknown
0
Affected Vendor
Mozilla
View all reports →Affected Software
Firefox
Vulnerable Versions:
< 86
Timeline
Official Publish:
February 26th, 2021
Last Modified:
August 3rd, 2024
Added to House:
July 21st, 2026
CVSS Vectors
V3:
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:N/A:N
Weaknesses (CWE)
No CWE data available
MITRE ATT&CK TTPs
No associated TTPs found for this vulnerability.