CVE-2024-39545: Junos OS: SRX Series, MX Series with SPC3 and NFX350: When VPN tunnels parameters are not configured in specific way the iked process will crash

Severity: high (CVSS 7.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.5% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2024-07-11 · updated 2026-06-17
Weakness: CWE-754

Description

An Improper Check for Unusual or Exceptional Conditions vulnerability in the the IKE daemon (iked) of Juniper Networks Junos OS on SRX Series, MX Series with SPC3 and NFX350 allows allows an unauthenticated, network-based attacker sending specific mismatching parameters as part of the IPsec negotiation to trigger an iked crash leading to Denial of Service (DoS). This issue is applicable to all platforms that run iked. This issue affects Junos OS on SRX Series, MX Series with SPC3 and NFX350: * All versions before 21.2R3-S8, * from 21.4 before 21.4R3-S7, * from 22.1 before 22.1R3-S2, * from 22.2 before 22.2R3-S1, * from 22.3 before 22.3R2-S1, 22.3R3, * from 22.4 before 22.4R1-S2, 22.4R2, 22.4R3.

Affected products

Juniper Junos OS: before 21.2; 21.2, 21.2-r1, 21.2-r1-s1, 21.2-r1-s2, 21.2-r2, 21.2-r2-s1 (+51) — fixed in 21.2

How to fix

Upgrade to a fixed version: Juniper Junos OS 21.2. Check the vendor advisory for mitigations.

References

Get alerted when CVE-2024-39545 or the next vulnerability affects your stack