CVE-2023-36844: Juniper Junos OS EX Series PHP External Variable Modification Vulnerability

Required action (CISA's text)

Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.

Description (NVD)

Juniper Junos OS on EX Series contains a PHP external variable modification vulnerability that allows an unauthenticated, network-based attacker to control certain, important environment variables. Using a crafted request an attacker is able to modify certain PHP environment variables, leading to partial loss of integrity, which may allow chaining to other vulnerabilities.

SOURCES

• CISA KEVCISA Known Exploited Vulnerabilities catalog

Other Juniper flaws

• CVE-2015-7755: Juniper ScreenOS Improper Authentication Vulnerability
• CVE-2025-21590: Juniper Junos OS Improper Isolation or Compartmentalization Vulnerability
• CVE-2023-36851: Juniper Junos OS SRX Series Missing Authentication for Critical Function Vulnerability
• CVE-2023-36847: Juniper Junos OS EX Series Missing Authentication for Critical Function Vulnerability
• CVE-2023-36846: Juniper Junos OS SRX Series Missing Authentication for Critical Function Vulnerability

Data from NVD, CISA KEV, FIRST EPSS and vendor advisories. Updated 10 Nov 2026.