CVE-2021-23973

When trying to load a cross-origin resource in an audio/video context a decoding error may have resulted, and the content of that error may have revealed information about the resource. This vulnerability affects Firefox < 86, Thunderbird < 78.8, and Firefox ESR < 78.8.

• CWE-209

• https://bugzilla.mozilla.org/show_bug.cgi?id=1690976Issue Tracking, Permissions Required, Vendor Advisory
• https://lists.debian.org/debian-lts-announce/2021/03/msg00000.htmlMailing List, Third Party Advisory
• https://security.gentoo.org/glsa/202104-09Third Party Advisory
• https://security.gentoo.org/glsa/202104-10Third Party Advisory
• https://www.debian.org/security/2021/dsa-4866Third Party Advisory
• https://www.mozilla.org/security/advisories/mfsa2021-07/Release Notes, Vendor Advisory
• https://www.mozilla.org/security/advisories/mfsa2021-08/Release Notes, Vendor Advisory
• https://www.mozilla.org/security/advisories/mfsa2021-09/Release Notes, Vendor Advisory
• https://bugzilla.mozilla.org/show_bug.cgi?id=1690976Issue Tracking, Permissions Required, Vendor Advisory
• https://lists.debian.org/debian-lts-announce/2021/03/msg00000.htmlMailing List, Third Party Advisory
• https://security.gentoo.org/glsa/202104-09Third Party Advisory
• https://security.gentoo.org/glsa/202104-10Third Party Advisory
• https://www.debian.org/security/2021/dsa-4866Third Party Advisory
• https://www.mozilla.org/security/advisories/mfsa2021-07/Release Notes, Vendor Advisory
• https://www.mozilla.org/security/advisories/mfsa2021-08/Release Notes, Vendor Advisory
• https://www.mozilla.org/security/advisories/mfsa2021-09/Release Notes, Vendor Advisory

Published

Feb 26, 2021

Last Modified

Jun 17, 2026

Status

Modified

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