# CVE-2023-36844: Junos OS - RCE

> Live exploitation tracking for CVE-2023-36844 by the CrowdSec Live Exploit Tracker, built from real-world attack data crowdsourced from CrowdSec's global network.

Page: https://tracker.crowdsec.net/cves/CVE-2023-36844

## Key facts

- **Exploitation phase:** Limited Exploitation. The vulnerability is known but shows very limited attacker interest or exploitation activity.
- **CVSS score:** 5.3
- **Public exploit available:** Yes
- **Affected products:** Juniper Networks Junos OS
- **Weaknesses:** CWE-473 (PHP External Variable Modification)
- **Tags:** enterprise_software, firewall

## 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.

## CrowdSec analysis

[CVE-2023-36844](https://euvd.enisa.europa.eu/vulnerability/CVE-2023-36844) is a vulnerability in the J-Web interface of Juniper Networks Junos OS, which enables unauthenticated attackers to modify critical environment variables through crafted requests.

CrowdSec has been tracking this vulnerability and its exploits since 1st of April 2025.

CrowdSec network data shows that most actors exploiting CVE-2023-36844 rely on broad, untargeted scans with minimal filtering. The activity is largely automated and opportunistic in nature.
Additionally, according to week-over-week analysis by CrowdSec, exploitation of CVE-2023-36844 is surging. Attack volumes are spiking well above historical norms, indicating widespread and escalating interest from threat actors. CVE-2023-36844 is currently experiencing high visibility and active exploitation across the internet.

Observed attack patterns are aimed at the `/webauth_operation.php` endpoint, focusing on systems with publicly exposed interfaces.

## Timeline

- 2023-08-17: CVE Published. CVE-2023-36844 is published to NVD.
- 2023-11-13: CISA KEV. CVE-2023-36844 is added to the Known Exploited Vulnerabilities catalog by CISA.
- 2023-11-17: CISA Remediation Deadline. Expiration of the CISA remediation deadline as described in [BOD 22-01](https://www.cisa.gov/news-events/directives/bod-22-01-reducing-significant-risk-known-exploited-vulnerabilities).
- 2025-04-01: Rule Released. CrowdSec releases a rule to detect CVE-2023-36844 exploitation attempts against the CrowdSec Network.
- 2025-04-01: CrowdSec First Seen. CrowdSec observes in-the-wild exploitation of CVE-2023-36844 for the first time.

## References

- https://github.com/projectdiscovery/nuclei-templates/blob/main/http/cves/2023/CVE-2023-36844.yaml

## Live exploitation data

The [Live Exploit Tracker page](https://tracker.crowdsec.net/cves/CVE-2023-36844) follows observed exploitation activity for CVE-2023-36844. [Request an API key](https://tracker.crowdsec.net/request-api-key) for full access to its exploitation timeline, attacking IP addresses and blocklists.