CVE-2023-36845criticalunder attackCWE-473

CVE-2023-36845: critical vulnerability in Juniper Networks Junos OS

Junos OS: EX and SRX Series: A PHP vulnerability in J-Web allows an unauthenticated to control an important environment variable

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100Vexday Risk Score

Patch now. It under exploitation confirmed by CISA and has a working public exploit.

ssvc Actcvss 9.8epss 95%
from disclosure to weaponsame day
Published on NVDAug 17
1st PoCApr 26
metasploitAug 17
CISA KEV+88d
Action required by CISAfederal deadline: 2023-11-17

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

In short

A flaw in Juniper's J-Web interface allows attackers to run malicious code on EX and SRX network devices without logging in. By sending a specially crafted request, an attacker can change how PHP executes and inject harmful commands.

Technical detail

CVE-2023-36845 is a PHP External Variable Modification (CWE-473) vulnerability in J-Web affecting Junos OS on EX and SRX Series. An unauthenticated attacker can craft HTTP requests that manipulate the PHPRC environment variable, enabling arbitrary code execution with the privileges of the web service. The vulnerability requires network access to the J-Web interface but no authentication or user interaction.

Summary generated and translated by AI from the official description.

The full analysis of this CVE is available in Portuguese →

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.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Affected products
Juniper Networks · Junos OS
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