PT-2026-56975 · Juniper Networks · Junos

Published 2026-07-09 · Updated 2026-07-09 · CVE-2026-57021

Mitre

CVSS v3.1

5.3

Medium

Base vector

AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L

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.

Fix

Memory Corruption

Weakness Enumeration

CWE-787

Related Identifiers

CVE-2026-57021

Affected Products

Junos

References · 2

• https://supportportal.juniper.net/JSA110081 · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2026-57021 · Security Note