CVE-2023-36844

Known Exploited Public Exploit
Junos OS: EX Series: A PHP vulnerability in J-Web allows an unauthenticated attacker to control important environment variables

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.

Remediation

Solution:

  • The following software releases have been updated to resolve this specific issue: 20.4R3-S9*, 21.2R3-S7*, 21.3R3-S5*, 21.4R3-S5*, 22.1R3-S4*, 22.2R3-S2, 22.3R3-S1*, 22.4R2-S2*, 22.4R3*, 23.2R1-S1, 23.2R2*, 23.4R1*, and all subsequent releases. *Pending Publication

Workaround:

  • Disable J-Web, or limit access to only trusted hosts.

Category

5.3
CVSS
Severity: Medium
CVSS 3.1 •
EPSS 94.30% Top 5%
KEV Since 
Vendor Advisory juniper.net
Affected: Juniper Networks Junos OS
Published at:
Updated at:

References

Link Tags
https://supportportal.juniper.net/JSA72300 mitigation vendor advisory
http://packetstormsecurity.com/files/174865/Juniper-SRX-Firewall-EX-Switch-Remote-Code-Execution.html third party advisory vdb entry exploit

Frequently Asked Questions

What is the severity of CVE-2023-36844?
CVE-2023-36844 has been scored as a medium severity vulnerability.
How to fix CVE-2023-36844?
To fix CVE-2023-36844: The following software releases have been updated to resolve this specific issue: 20.4R3-S9*, 21.2R3-S7*, 21.3R3-S5*, 21.4R3-S5*, 22.1R3-S4*, 22.2R3-S2, 22.3R3-S1*, 22.4R2-S2*, 22.4R3*, 23.2R1-S1, 23.2R2*, 23.4R1*, and all subsequent releases. *Pending Publication
Is CVE-2023-36844 being actively exploited in the wild?
It is confirmed that CVE-2023-36844 is actively exploited. Be extra cautious if you are using vulnerable components. According to its EPSS score, there is a ~94% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2023-36844?
CVE-2023-36844 affects Juniper Networks Junos OS.
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