CVE-2026-57021Junos OS: SRX Series: If VPN compliance-check is configured an attacker can cause http-gk process crash
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.
Overview
Severity
| Score | Severity | Version | Vector String |
|---|---|---|---|
| 6.9 | MEDIUM | 4.0juniper (CNA) | 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 |
| 5.3 | MEDIUM | 3.1juniper (CNA) | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L |
Details
- CVE ID
- CVE-2026-57021
- Status
- Analyzed
- Assigner (CNA)
- juniper
- Published
- Jul 9, 2026
- Last modified
- 2026-10-25 15:10 UTC
- Weaknesses
- CWE-787 · Out-of-bounds Write
Affected Products
As published by the CNA in the CVE record.
Juniper NetworksJunos OS6 version ranges
- 23.2 before 23.2R2-S7
- 23.4 before 23.4R2-S8
- 24.2 before 24.2R2-S4
- 24.4 before 24.4R2-S4
- 25.2 before 25.2R2
- 25.4 before 25.4R1-S1, 25.4R2