# CVE-2023-36844: Junos OS: EX Series: A PHP vulnerability in J-Web allows an unauthenticated attacker to control important environment variables

> CVE-2023-36844: Junos OS: EX Series: A PHP vulnerability in J-Web allows an unauthenticated attacker to control important environment variables. CVSS 5.3 (CVSS 3.1), in CISA KEV.

Canonical: https://rewindex.com/cve/CVE-2023-36844
Last updated: 2025-10-21T23:05:40Z

- Published: 2023-08-17 19:17 UTC · Updated: 2025-10-21 23:05 UTC · Assigner: juniper
- CVSS: 5.3 (CVSS 3.1) · Severity: Medium · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
- EPSS: 90.0%, 100th percentile (scored 2026-10-25)
- CISA KEV: yes, added 2023-11-13, federal due date 2023-11-17, ransomware use: Unknown
- CWE: CWE-473

## Description

A PHP External Variable Modification vulnerability in J-Web of Juniper Networks Junos OS on EX Series 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. This issue affects Juniper Networks Junos OS on 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 22.3R3-S1;   \*  22.4 versions  prior to  22.4R2-S2, 22.4R3;   \*  23.2 versions prior to  23.2R1-S1, 23.2R2.

## CISA required action

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

## Affected vendors and products

- Juniper Networks: Junos OS

## References

- [CVE record on cve.org](https://www.cve.org/CVERecord?id=CVE-2023-36844)
- [NVD entry](https://nvd.nist.gov/vuln/detail/CVE-2023-36844)
- [http://packetstormsecurity.com/files/174865/Juniper-SRX-Firewall-EX-Switch-Remote-Code-Execution.html](http://packetstormsecurity.com/files/174865/Juniper-SRX-Firewall-EX-Switch-Remote-Code-Execution.html)
- [https://supportportal.juniper.net/JSA72300](https://supportportal.juniper.net/JSA72300)

---

_Sources: CVE records from the CVE Program (cve.org). CVE® is a registered trademark of The MITRE Corporation. (https://www.cve.org/) This product uses data from the NVD API but is not endorsed or certified by the NVD. (https://nvd.nist.gov/) Known Exploited Vulnerabilities catalog from CISA. (https://www.cisa.gov/known-exploited-vulnerabilities-catalog) EPSS scores from FIRST (Exploit Prediction Scoring System). (https://www.first.org/epss/)_


---
Canonical: https://rewindex.com/cve/CVE-2023-36844 · Markdown: https://rewindex.com/cve/CVE-2023-36844.md · JSON: https://rewindex.com/api/v1/cves/CVE-2023-36844 · Data licensed CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/) · Generated 2026-10-26T03:09:55.177Z