CVE-2019-17023

After a HelloRetryRequest has been sent, the client may negotiate a lower protocol that TLS 1.3, resulting in an invalid state transition in the TLS State Machine. If the client gets into this state, incoming Application Data records will be ignored. This vulnerability affects Firefox < 72.

• CWE-287

• https://bugzilla.mozilla.org/show_bug.cgi?id=1590001Issue Tracking, Permissions Required
• https://usn.ubuntu.com/4234-1/Third Party Advisory
• https://usn.ubuntu.com/4397-1/Third Party Advisory
• https://www.debian.org/security/2020/dsa-4726Third Party Advisory
• https://www.mozilla.org/security/advisories/mfsa2020-01/Vendor Advisory
• https://bugzilla.mozilla.org/show_bug.cgi?id=1590001Issue Tracking, Permissions Required
• https://usn.ubuntu.com/4234-1/Third Party Advisory
• https://usn.ubuntu.com/4397-1/Third Party Advisory
• https://www.debian.org/security/2020/dsa-4726Third Party Advisory
• https://www.mozilla.org/security/advisories/mfsa2020-01/Vendor Advisory

Published

Jan 8, 2020

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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