# CVE-2023-36844

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.

- Page: https://www.vulneraibility.com/cve/CVE-2023-36844
- CVSS: 5.3
- Known exploited: yes, in CISA KEV since 2023-11-13; CISA due date 2023-11-17
- EPSS: 89.96% (percentile 99.8)
- Unvetted proof-of-concept code on GitHub: 3 GitHub proofs of concept · 1 Nuclei template (first 2023-08-25)
- CISA SSVC: exploitation active, automatable yes, technical impact total (assessed 2023-11-15)
- Weakness: CWE-473
- Published: 2023-08-17

## Affected versions

- Juniper Networks Junos OS: affected < 20.4R3-S9; >= 21.1 and < 21.1*; >= 21.2 and < 21.2R3-S6; >= 21.3 and < 21.3R3-S5; >= 21.4 and < 21.4R3-S5; >= 22.1 and < 22.1R3-S4; >= 22.2 and < 22.2R3-S2; >= 22.3 and < 22.3R3-S1; >= 22.4 and < 22.4R2-S2, 22.4R3; >= 23.2 and < 23.2R1-S1, 23.2R2

A version outside these ranges is not a statement that it is unaffected.

## References

- [advisory] https://supportportal.juniper.net/JSA72300
- [other] http://packetstormsecurity.com/files/174865/Juniper-SRX-Firewall-EX-Switch-Remote-Code-Execution.html
- [other] https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2023-36844

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Summary, impact and action are written by the vulneraibility.com AI analysis pipeline from the CVE record, NVD, CISA and FIRST data; verify against the references.