CVE-2026-57021
published 2026-07-09CVE-2026-57021: 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…
PriorityP335medium5.3CVSS 3.1
AVNACLPRNUINSUCNINAL
EPSS
0.47%
37.9th percentile
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.
Affected
51 ranges· showing 25
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CVSS provenance
nvdv3.15.3MEDIUMCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
nvdv4.06.9MEDIUMCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:Y/R:A/V:X/RE:M/U:X
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VulDB
Juniper Junos OS up to 25.4R1-S1 Http-Gatekeeper out-of-bounds write
vuldb·2026-07-10·CVSS 5.3
CVE-2026-57021 [MEDIUM] Juniper Junos OS up to 25.4R1-S1 Http-Gatekeeper out-of-bounds write
A vulnerability, which was classified as critical, has been found in Juniper Junos OS up to 25.4R1-S1. The impacted element is an unknown function of the component Http-Gatekeeper. This manipulation causes out-of-bounds write.
The identification of this vulnerability is CVE-2026-57021. It is possible to initiate the attack remotely. There is no exploit available.
GHSA
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).
ghsa_unreviewed·2026-07-10
CVE-2026-57021 [MEDIUM] CWE-787 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).
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,
* 2
No detection rules found.
No public exploits indexed.
No writeups or analysis indexed.
2026-07-09
Published