CVEs / CVE-2023-36851
CVE-2023-36851: Juniper Junos OS SRX Series Missing Authentication for Critical Function Vulnerability
- Known exploited in the CISA KEV catalog since 13 Nov 2023
- medium 5.3 CVSS 3.1 (NVD)
- EPSS 1.12% chance of exploitation in the next 30 days, higher than 66% of CVEs (30 Oct 2026)
- Last changed at its sources
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Summary
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.
Description
A Missing Authentication for Critical Function vulnerability in Juniper Networks Junos OS on SRX Series 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 and download arbitrary files via J-Web, leading to a loss of integrity or confidentiality, which may allow chaining to other vulnerabilities. This issue affects Juniper Networks Junos OS on SRX Series: * 21.2 versions prior to 21.2R3-S8; * 21.4 versions prior to 21.4R3-S6; * 22.1 versions prior to 22.1R3-S5; * 22.2 versions prior to 22.2R3-S3; * 22.3 versions prior to 22.3R3-S2; * 22.4 versions prior to 22,4R2-S2, 22.4R3; * 23.2 versions prior to 23.2R1-S2, 23.2R2.
Affected and fixed versions
| Product | Affected | Fixed in |
|---|---|---|
| Juniper Networks Junos OS | from 21.2, before 21.2R3-S8 | 21.2R3-S8 |
| Juniper Networks Junos OS | from 21.4, before 21.4R3-S6 | 21.4R3-S6 |
| Juniper Networks Junos OS | from 22.1, before 22.1R3-S5 | 22.1R3-S5 |
| Juniper Networks Junos OS | from 22.2, before 22.2R3-S3 | 22.2R3-S3 |
| Juniper Networks Junos OS | from 22.3, before 22.3R3-S2 | 22.3R3-S2 |
| Juniper Networks Junos OS | from 22.4, before 22.4R2-S2, 22.4R3 | 22.4R2-S2, 22.4R3 |
| Juniper Networks Junos OS | from 23.2, before 23.2R1-S2, 23.2R2 | 23.2R1-S2, 23.2R2 |
Exploitation
| In CISA KEV since | 13 Nov 2023 |
|---|---|
| Due date for US federal agencies | 17 Nov 2023 |
| Used in ransomware campaigns | Unknown |
| Required action | Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable. |
Severity
| CVSS 3.1 | 5.3 mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:NScored by NVD |
|---|---|
| Weakness | CWE-306 |
References
- CVE-2023-36851 on NVD
- CVE-2023-36851 in the CISA KEV catalog
- 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 (cited by CISA)
- https://supportportal.juniper.net/JSA72300 Vendor Advisory
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2023-36851 US Government Resource
Sources
Exploitation status from the CISA Known Exploited Vulnerabilities catalog. EPSS scores from FIRST. Descriptions, severity and references from the National Vulnerability Database. Open-source package versions from OSV (CC-BY 4.0). Text is shown as each source states it; Stackurity does not edit it. Check the vendor's advisory before acting.
This product uses data from the NVD API but is not endorsed or certified by the NVD.