CVE-2026-57021 PUBLISHED

Junos OS: SRX Series: If VPN compliance-check is configured an attacker can cause http-gk process crash

Assigner: juniper
Reserved: 23.06.2026 Published: 09.07.2026 Updated: 10.07.2026

An Out-of-bounds Write vulnerability in the http-gatekeeper (http-gk) of Juniper Networks Junos OS on SRX Series allows an unauthenticated, network-based attacker to cause a Denial-of-Service (DoS).

If an SRX Series device is configured for remote-access VPN with pre-logon compliance check, a network-based attacker sending specifically formatted requests can trigger an out of bounds write leading to an http-gk process crash. This crash leads to unavailability of all services depending on the [ system services web-management ] configuration (like J-Web, remote access VPN and firewall authentication) until the process automatically restarts.

This issue affects Junos OS on SRX Series:

  • 23.2 versions before 23.2R2-S7,
  • 23.4 versions before 23.4R2-S8,
  • 24.2 versions before 24.2R2-S4,
  • 24.4 versions before 24.4R2-S4,
  • 25.2 versions before 25.2R2,
  • 25.4 versions before 25.4R1-S1, 25.4R2.

Metrics

CVSS Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/AU:Y/R:A/RE:M
CVSS Score: 6.9

Product Status

Vendor Juniper Networks
Product Junos OS
Versions Default: unaffected
  • affected from 23.2 to 23.2R2-S7 (excl.)
  • affected from 23.4 to 23.4R2-S8 (excl.)
  • affected from 24.2 to 24.2R2-S4 (excl.)
  • affected from 24.4 to 24.4R2-S4 (excl.)
  • affected from 25.2 to 25.2R2 (excl.)
  • affected from 25.4 to 25.4R1-S1, 25.4R2 (excl.)

Affected Configurations

To be exposed to this issue, the device needs to be configured to perform client compliance checks with:

[ security remote-access compliance pre-logon ... ]

Exploits

Juniper SIRT is not aware of any malicious exploitation of this vulnerability.

Workarounds

There are no known workarounds for this issue.

Solutions

The following software releases have been updated to resolve this specific issue:

Junos OS: 23.2R2-S7, 23.4R2-S8, 24.2R2-S4, 24.4R2-S4, 25.2R2, 25.4R1-S1, 25.4R2, 26.2R1, and all subsequent releases.

References

Problem Types

  • CWE-787 Out-of-bounds Write CWE