CVE-2026-94200: CWE-1288 Improper Validation of Consistency within Input in Erlang OTP

This vulnerability arises because the TLS 1.3 client incorrectly decodes extensions of a NewSessionTicket message as if they were from EncryptedExtensions, accepting a 0-length early_data extension which is only valid in ClientHello and EncryptedExtensions. When session tickets are stored automatically, the client crashes on resumption due to a case_clause failure in tls_handshake_1_3:get_max_early_data/1. Repeated crashes exceed the restart intensity of ssl supervisors using a rest_for_one strategy, causing the ssl application to become unavailable for all connections on the node. The affected versions include Erlang OTP from 23.3 before 27.3.4.19 and ssl from 10.3 before 11.2.12.14, as well as some other specified versions.

Successful exploitation results in a denial of service of the ssl application on the client node, disrupting all SSL/TLS connections managed by that node. This can cause service outages or degraded availability for applications relying on Erlang OTP's ssl module for secure communications. There is no indication of privilege escalation or data disclosure.

Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Since no explicit patch links are provided, users should monitor Erlang/OTP official advisories for updates addressing this vulnerability. Until a fix is applied, consider disabling automatic session ticket resumption or avoid connecting to untrusted TLS 1.3 servers that might exploit this flaw.