CVE-2023-36847
Junos OS: EX Series: A vulnerability in J-Web allows an unauthenticated attacker to upload arbitrary files
Juniper Junos OS EX Series Missing Authentication for Critical Function Vulnerability is confirmed as actively exploited and is listed in the CISA KEV catalog.
Required action
Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.
CISA notes
https://supportportal.juniper.net/s/article/2023-08-Out-of-Cycle-Security-Bulletin-Junos-OS-SRX-Series-and-EX-Series-Multiple-vulnerabilities-in-J-Web-can-be-combined-to-allow-a-preAuth-Remote-Code-Execution?language=en_US; https://nvd.nist.gov/vuln/detail/CVE-2023-36847
Description
A Missing Authentication for Critical Function vulnerability in Juniper Networks Junos OS on EX Series allows an unauthenticated, network-based attacker to cause limited impact to the file system integrity. With a specific request to installAppPackage.php that doesn't require authentication an attacker is able to upload arbitrary files via J-Web, leading to a loss of integrity for a certain part of the file system, which may allow chaining to other vulnerabilities. This issue affects Juniper Networks Junos OS on EX Series: * All versions prior to 20.4R3-S8; * 21.1 versions 21.1R1 and later; * 21.2 versions prior to 21.2R3-S6; * 21.3 versions prior to 21.3R3-S5; * 21.4 versions prior to 21.4R3-S4; * 22.1 versions prior to 22.1R3-S3; * 22.2 versions prior to 22.2R3-S1; * 22.3 versions prior to 22.3R2-S2, 22.3R3; * 22.4 versions prior to 22.4R2-S1, 22.4R3.
Severity
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:NExploitation Context
as of October 14, 2026- CISA added CVE-2023-36847 to the KEV catalog 88 days after its CVE record was published. The median for entries added in 2023 is 12 days.
- It is one of 8 Juniper entries in the CISA KEV catalog, and one of 5 added in 2023.
- Its current EPSS score (83.5%) is higher than that of 66% of CISA KEV entries.
Affected Products
| Vendor | Product | Affected versions |
|---|---|---|
| Juniper Networks | Juniper Networks Junos OS | 0 to <20.4R3-S8 21.1 to <21.1* 21.2 to <21.2R3-S6 21.3 to <21.3R3-S5 21.4 to <21.4R3-S4 22.1 to <22.1R3-S3 22.2 to <22.2R3-S1 22.3 to <22.3R2-S2, 22.3R3 22.4 to <22.4R2-S1, 22.4R3 |
References
1 LinksRecord Details
More from Juniper Networks
Junos OS: EX and SRX Series: A PHP vulnerability in J-Web allows an unauthenticated to control an important environment variable
Junos OS: SRX Series: A vulnerability in J-Web allows an unauthenticated attacker to upload arbitrary files
Junos OS: EX Series: A PHP vulnerability in J-Web allows an unauthenticated attacker to control important environment variables
Out of Cycle Security Advisory: Junos OS: Security vulnerability in J-Web and web based (HTTP/HTTPS) services
Related
Tool categories
CVE record data © The MITRE Corporation, used under the CVE Terms of Use. Exploited-in-the-wild data from the CISA Known Exploited Vulnerabilities catalog (CC0). Exploit prediction scores by FIRST EPSS (first.org/epss). This site is not endorsed or certified by MITRE, NVD, CISA, or FIRST.