CVE-2026-57024: Junos OS: MX with SPC3, SRX Series: Repeated VPN negotiation failures will eventually cause iked to crash continuously

A Use of Multiple Resources with Duplicate Identifier vulnerability in the IKE daemon (iked) of Juniper Networks Junos OS on MX with SPC3 and SRX Series allows an unauthenticated, network-based attacker to cause a Denial-of-Service (DoS).

On an MX with SPC3 and SRX devices configured for VPN service, when a large number of VPN negotiations fail a peer index rollover will eventually occur. As a result, new peers are assigned index values that are already in use and the iked process starts to crash repeatedly. This results in failure to establish new VPN connections and rekeying existing ones. To restore service the system must be rebooted. Please note that the index value can't be monitored, so customers should monitor tunnel up and down events and if a lot of events occur over an extended period of time it becomes likely that this issue occurs.

To be exposed to this issue the system needs to run iked (vs. kmd which is not affected), which can be verified with:

user@host> show system processes extensive | match "KMD|IKED" This issue affects Junos OS on MX with SPC3, SRX Series:

all versions before 23.2R2-S7, 23.4 versions before 23.4R2-S6, 24.2 versions before 24.2R2-S3, 24.4 versions before 24.4R2-S4, 25.2 versions before 25.2R1-S1.