CVE-2026-94200 TLS 1.3 client ticket store crashed by NewSessionTicket with empty early_data extension in ssl
- Exploited in the wild
- Not known
- Fix
- Available
What is CVE-2026-94200?
CVE-2026-94200 is a high-severity vulnerability in Erlang OTP, published on 14 Oct 2026.
Official description
Improper Validation of Consistency within Input vulnerability in Erlang OTP ssl (tls_handshake_1_3, ssl_handshake and tls_client_ticket_store modules) allows a malicious TLS 1.3 server to cause a denial of service of the ssl application on the client node.
The TLS 1.3 client decodes the extensions of a NewSessionTicket message as if they came from EncryptedExtensions. It therefore accepts a 0-length early_data extension, a form that is only valid in ClientHello and EncryptedExtensions. With {session_tickets, auto}, the client stores the ticket in the node-global tls_client_ticket_store. On the next automatic resumption, tls_handshake_1_3:get_max_early_data/1 crashes the store with a case_clause. Repeated crashes can exceed the restart intensity of the ssl supervisors, which use the rest_for_one strategy, and take down ssl for all connections on the node.
This issue affects OTP from OTP 23.3 before OTP 27.3.4.19, OTP 28.5.0.8, and OTP 29.1.2, corresponding to ssl from 10.3 before 11.2.12.14, 11.6.0.7, and 11.7.8.
Weakness: CWE-1288
Which versions are affected by CVE-2026-94200?
How do I fix CVE-2026-94200?
Upgrade to a fixed version.
Is CVE-2026-94200 being exploited?
There is no known exploitation of CVE-2026-94200 in the wild and no public exploit code.
Sources
Also known as AZL-108204, DEBIAN-CVE-2026-94200, EEF-CVE-2026-94200, GHSA-m5mh-q53w-67jq, UBUNTU-CVE-2026-94200.