# CVE-2023-36845: Juniper Junos OS EX Series and SRX Series PHP External Variable Modification Vulnerability

- Exploited (CISA KEV): yes, added 2023-11-13
- Published: 2023-08-17
- CVSS: 9.8 CRITICAL (v3.1)
- EPSS: 95.1% (100th percentile)
- CWE: CWE-473

A PHP External Variable Modification vulnerability in J-Web of Juniper Networks Junos OS on EX Series 

and SRX Series 

allows an unauthenticated, network-based attacker to remotely execute code.

Using a crafted request which sets the variable PHPRC an attacker is able to modify the PHP execution environment allowing the injection und execution of code.


This issue affects Juniper Networks Junos OS on EX Series


and 


SRX Series:



  *  All versions prior to 

20.4R3-S9;
  *  21.1 versions 21.1R1 and later;
  *  21.2 versions prior to 21.2R3-S7;
  *  21.3 versions prior to 21.3R3-S5;
  *  21.4 versions prior to 21.4R3-S5;
  *  22.1 versions 

prior to 

22.1R3-S4;
  *  22.2 versions 

prior to 

22.2R3-S2;
  *  22.3 versions 

prior to 

22.3R2-S2, 22.3R3-S1;
  *  22.4 versions 

prior to 

22.4R2-S1, 22.4R3;
  *  23.2 versions prior to 23.2R1-S1, 23.2R2.

## Edge WAF coverage (claimed by vendors, not measured)

| Vendor | Status | First rule | Days after publication |
|---|---|---|---|
| Cloudflare | Before feed history | — | — |
| AWS | No public claim | — | — |
| Microsoft Azure | No public claim | — | — |
| Google Cloud | Before feed history | — | — |
| Fastly | Before feed history | — | — |
| F5 | Rule published | 2023-12-12 | 117 |
| Akamai | No public source | — | — |
| OWASP CRS | No public claim | — | — |

### F5

- 2023-12-12 · new · rule 200103328
  > Added: signature 200103328 "Juniper JunOS PHP Remote Code Execution" (Command Execution, risk High), systems: PHP. References: CVE-2023-36845.
  Source: https://docs.cloud.f5.com/docs-v2/platform/changelogs/security-details-changelog

## Our test (measured)

- OWASP Core Rule Set 4.25.0, paranoia level 1, anomaly threshold 5, default CRS settings: blocked (1 of 1 requests blocked), template CVE-2023-36845, 2026-11-02
- OWASP Core Rule Set 4.25.0, paranoia level 2, anomaly threshold 5, default CRS settings: blocked (1 of 1 requests blocked), template CVE-2023-36845, 2026-11-02

"No public claim" means no vendor statement names this CVE; "Before feed history" means the CVE is older than the vendor feed. In both cases generic rules may still block it.

HTML: https://cve.vigilbase.com/cve/CVE-2023-36845 · JSON: https://cve.vigilbase.com/api/v1/cves/CVE-2023-36845