CVE-2023-36844 is a vulnerability in Juniper Networks Junos
Published on August 17, 2023
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.
Known Exploited Vulnerability
This Juniper Junos OS EX Series PHP External Variable Modification Vulnerability is part of CISA's list of Known Exploited Vulnerabilities. Juniper Junos OS on EX Series contains a PHP external variable modification vulnerability that 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.
The following remediation steps are recommended / required by November 17, 2023: Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.
Vulnerability Analysis
CVE-2023-36844 is exploitable with network access, and does not require authorization privileges or user interaction. This vulnerability is considered to have a low attack complexity. This vulnerability is known to be actively exploited by threat actors in an automatable fashion. The potential impact of an exploit of this vulnerability is considered to have no impact on confidentiality, with no impact on integrity, and no impact on availability.
Weakness Type
PHP External Variable Modification
A PHP application does not properly protect against the modification of variables from external sources, such as query parameters or cookies. This can expose the application to numerous weaknesses that would not exist otherwise.
Products Associated with CVE-2023-36844
You can be notified by email with stack.watch whenever vulnerabilities like CVE-2023-36844 are published in Juniper Networks Junos:
Affected Versions
Juniper Networks Junos OS:- Before 20.4R3-S9 is affected.
- Version 21.1 and below 21.1* is affected.
- Version 21.2 and below 21.2R3-S6 is affected.
- Version 21.3 and below 21.3R3-S5 is affected.
- Version 21.4 and below 21.4R3-S5 is affected.
- Version 22.1 and below 22.1R3-S4 is affected.
- Version 22.2 and below 22.2R3-S2 is affected.
- Version 22.3 and below 22.3R3-S1 is affected.
- Version 22.4 and below 22.4R2-S2, 22.4R3 is affected.
- Version 23.2 and below 23.2R1-S1, 23.2R2 is affected.
Exploit Probability
EPSS (Exploit Prediction Scoring System) scores estimate the probability that a vulnerability will be exploited in the wild within the next 30 days. The percentile shows you how this score compares to all other vulnerabilities.