CVE-2026-33778

Summary

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.

Affected Software

VendorProductVersion RangeStatus
Juniper NetworksJunos OS0 < 22.4R3-S9affected
Juniper NetworksJunos OS23.2 < 23.2R2-S6affected
Juniper NetworksJunos OS23.4 < 23.4R2-S7affected
Juniper NetworksJunos OS24.2 < 24.2R2-S4affected
Juniper NetworksJunos OS24.4 < 24.4R2-S3affected
Juniper NetworksJunos OS25.2 < 25.2R1-S2, 25.2R2affected

Weaknesses

  • CWE-1286: CWE-1286 Improper Validation of Syntactic Correctness of Input

Workarounds

There are no known workarounds for this issue.

ADP Enrichment

CISA ADP Vulnrichment

  • SSVC:
  • Exploitation: none
    • Automatable: yes
    • Technical Impact: partial

References