Last Modified: Jul 28, 2026
Affected Product(s):
BIG-IP LTM
Fixed In:
17.5.1.8, 17.1.3.4
Opened: Jan 28, 2026 Severity: 3-Major
When deploying a valid HTTP/3 virtual server on a PAYG AWS BIG-IP instance, HTTP/3 requests periodically encounter ERR_HANDSHAKE_TIMEOUT or ERR_IDLE_CLOSE errors. Examples of error messages include: =========== messages: curl: (55) ngtcp2_conn_handle_expiry returned error: ERR_HANDSHAKE_TIMEOUT OR curl: (56) ngtcp2_conn_handle_expiry returned error: ERR_IDLE_CLOSE ===========
All QUIC/HTTP3 handshakes are rejected by the virtual server.
The BIG-IP virtual server is configured to support HTTP/3 QUIC traffic. The BIG-IP system is operating in FIPS mode
None
Resolved the issue by fixing the cipher and algorithm calculation.