CVE-2023-36851
Juniper Junos OS SRX Series Missing Authentication for Critical Function Vulnerability
Juniper Junos OSNetwork & edge
CVSS
5.3MediumExploit odds (EPSS)1.12%Chance of exploitation activity in the next 30 days, higher than 65% of CVEs. Scored 23 Oct 2026FIRST EPSS
CISA required actionApply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable. CISA KEV
What fixes it
- 21.2R3-S8Junos OSCVE List
- 21.4R3-S6Junos OSCVE List
- 22.1R3-S5Junos OSCVE List
- 22.2R3-S3Junos OSCVE List
- 22.3R3-S2Junos OSCVE List
- 22.4R2-S2, 22.4R3Junos OSCVE List
Show all 7 fixed versions
- 23.2R1-S2, 23.2R2Junos OSCVE List
A fixed version on one release line is not the upgrade target for every line. Check your exact version and any vendor backports.
Timeline
Description
Juniper Junos OS on SRX Series contains a missing authentication for critical function vulnerability that allows an unauthenticated, network-based attacker to cause limited impact to the file system integrity. With a specific request to webauth_operation.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.
Text from CVE List
Affected versions 7
- Junos OSaffected: 21.2 before 21.2R3-S8CVE List
- Junos OSaffected: 21.4 before 21.4R3-S6CVE List
- Junos OSaffected: 22.1 before 22.1R3-S5CVE List
- Junos OSaffected: 22.2 before 22.2R3-S3CVE List
- Junos OSaffected: 22.3 before 22.3R3-S2CVE List
- Junos OSaffected: 22.4 before 22.4R2-S2, 22.4R3CVE List
- Junos OSaffected: 23.2 before 23.2R1-S2, 23.2R2CVE List
References 4
- 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_USAdvisoryvia CISA KEV
- supportportal.juniper.net/JSA72300Advisoryvia CVE List
- nvd.nist.gov/vuln/detail/CVE-2023-36851Referencevia CISA KEV
- cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2023-36851Referencevia CVE List