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

Source: https://junglewise.ai/threats/cve-2023-36845-juniper-junos-os-ex-series-and-srx-series-php-external-variable  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2023-11-13. Updated: 2026-05-09  
License: CC BY 4.0 with a link back

CVE-2023-36845 · Severity: critical · CVSS 9.8 · Exploited in the wild · Published 2023-11-13

A PHP External Variable Modification vulnerability in J-Web of Juniper Networks Junos OS allows an unauthenticated, network-based attacker to remotely execute code. By sending a crafted request that sets the PHPRC environment variable, an attacker can modify the PHP execution environment to inject and execute arbitrary code.

Technologies: [Juniper Junos OS](https://junglewise.ai/threats/technologies/junos-os). Vendors: [Juniper](https://junglewise.ai/threats/vendors/juniper).

## Quick answers

**Is CVE-2023-36845 exploited in the wild?** Yes. CVE-2023-36845 is known to be exploited in the wild, first recorded on 13 November 2023. Treat it as urgent.

**How severe is CVE-2023-36845?** Critical severity, with a CVSS score of 9.8, published 13 November 2023.

**Which products and versions are affected?** Juniper Networks Junos OS EX 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.; Juniper Networks Junos OS 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..

**Is there a fix for CVE-2023-36845?** No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

**How is CVE-2023-36845 attacked?** It is attacked over the network, in an operating system.

**Am I affected by CVE-2023-36845?** Check whether you run Juniper Junos OS. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Affected products

- Juniper Networks Junos OS EX 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.
- Juniper Networks Junos OS 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.

## Timeline

- 2023-11-13: disclosed
- 2023-11-13: kev added: Added to CISA Known Exploited Vulnerabilities Catalog

## Related threats

- [Juniper Junos OS Improper Isolation or Compartmentalization Vulnerability](https://junglewise.ai/threats/cve-2025-21590-juniper-junos-os-improper-isolation-or-compartmentalization)
- [Juniper Junos OS EX Series PHP External Variable Modification Vulnerability](https://junglewise.ai/threats/cve-2023-36844-juniper-junos-os-ex-series-php-external-variable-modification)
- [Juniper Junos OS SRX Series Missing Authentication for Critical Function Vulnerability](https://junglewise.ai/threats/cve-2023-36846-juniper-junos-os-srx-series-missing-authentication-for-critical)
- [Juniper Junos OS EX Series Missing Authentication for Critical Function Vulnerability](https://junglewise.ai/threats/cve-2023-36847-juniper-junos-os-ex-series-missing-authentication-for-critical)
- [Juniper Junos OS SRX Series Missing Authentication for Critical Function Vulnerability](https://junglewise.ai/threats/cve-2023-36851-juniper-junos-os-srx-series-missing-authentication-for-critical)