CVE-2021-23977

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.

• CWE-367

• https://bugzilla.mozilla.org/show_bug.cgi?id=1684761Issue Tracking, Permissions Required, Vendor Advisory
• https://security.gentoo.org/glsa/202104-10Third Party Advisory
• https://www.mozilla.org/security/advisories/mfsa2021-07/Release Notes, Vendor Advisory
• https://bugzilla.mozilla.org/show_bug.cgi?id=1684761Issue Tracking, Permissions Required, Vendor Advisory
• https://security.gentoo.org/glsa/202104-10Third Party Advisory
• https://www.mozilla.org/security/advisories/mfsa2021-07/Release Notes, Vendor Advisory

Published

Feb 26, 2021

Last Modified

Jun 17, 2026

Status

Modified

• How Strix found a critical auth bypass in etcdStrix autonomously discovered a critical authentication bypass in etcd, later designated CVE-2026-33413.
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