CVE-2023-36845
Juniper Junos ≤ 20.4
Raw vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HSummary
CVE-2023-36845 is a critical-severity PHP External Variable Modification (CWE-473) vulnerability in Juniper Junos. Its CVSS base score is 9.8 (Critical).
Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked in the top 0.2% of CVEs by exploit likelihood; CISA has added it to the Known Exploited Vulnerabilities catalog; a public proof-of-concept is referenced.
Deeper analysis AI-assisted summary
Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.
CVE-2023-36845 is a PHP External Variable Modification vulnerability in the J-Web interface of Juniper Networks Junos OS on EX Series and SRX Series platforms. An unauthenticated network attacker can supply a crafted request that sets the PHPRC variable, altering the PHP execution environment to permit injection and execution of arbitrary code. The flaw affects all versions prior to 20.4R3-S9, 21.2R3-S7, 21.3R3-S5, 21.4R3-S5, 22.1R3-S4, 22.2R3-S2, 22.3R2-S2/22.3R3-S1, 22.4R2-S1/22.4R3, and 23.2R1-S1/23.2R2, as well as 21.1R1 and later releases before the listed fixes.
An unauthenticated remote attacker can exploit the issue over the network to achieve full remote code execution with no user interaction or credentials required, corresponding to the CVSS 9.8 rating.
The official Juniper advisory JSA72300 directs customers to install the fixed releases enumerated above; no other workarounds are specified in the reference materials.
Public exploit code for the vulnerability has been posted to Packet Storm, and the EPSS score has reached a peak of 0.9719 with a current value of 0.9435, indicating sustained exploitation interest after disclosure.
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2023-40765
Vulnerability Data
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…
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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.
- CWE(s)
- KEV Date Added
- 13 November 2023
Related Threats
MITRE ATT&CK Enterprise Techniques
CVEs Like This One
Affected Assets
Mitigating Controls
Control response
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V1.2.4V15.3.5V15.3.7
Mitigating Controls (NIST CSF 2.0) AI
Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.
Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI
Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.
Security testing can detect variable-injection flaws but does not itself implement the preventive controls.
Secure development lifecycle mandates input validation and variable handling rules that directly prevent external variable tampering.
Application security requirements explicitly call for protection against tainted input sources such as query parameters and cookies.
Secure coding standards require disabling register_globals and sanitizing all external inputs, eliminating the root cause of CWE-473.
Information access restriction limits what data users can reach, indirectly reducing impact of tampered variables.