CVE-2026-33778
CWE-1286Published: April 9, 2026· Updated: Apr 13, 2026
Official Description
An Improper Validation of Syntactic Correctness of Input vulnerability in the IPsec library used by kmd and iked of Juniper Networks Junos OS on SRX Series and MX Series allows an unauthenticated, network-based attacker to cause a complete Denial-of-Service (DoS).
If an affected device receives a specifically malformed first ISAKMP packet from the initiator, the kmd/iked process will crash and restart, which momentarily prevents new security associations (SAs) for from being established. Repeated exploitation of this vulnerability causes a complete inability to establish new VPN connections.
This issue affects Junos OS on
SRX Series and MX Series:
* all versions before 22.4R3-S9,
* 23.2 version before 23.2R2-S6,
* 23.4 version before 23.4R2-S7,
* 24.2 versions before 24.2R2-S4,
* 24.4 versions before 24.4R2-S3,
* 25.2 versions before 25.2R1-S2, 25.2R2.
Technical Analysis
CVE-2026-33778 can be exploited remotely over the network without requiring physical or adjacent access, significantly expanding the attack surface for threat actors.
The vulnerability requires no privileges and no user interaction, making it a prime target for automated exploitation campaigns and worm-like propagation.
A successful exploit results in availability disruption (denial of service), with a CVSS base score of 7.5.
CVSS v3.1 Vector Breakdown
Affected Vendors & Products
Exploit & PoC Resources
All References (1)
Quick Facts
Related CVEs (CWE-1286)
Recommended Actions
- →Apply vendor patches immediately
- →Monitor CVE-2026-33778 in threat intel feeds
- →Review IDS/IPS signatures for exploitation attempts