Vulnerability · Published Oct 14, 2026 · Assigned by juniper
CVE-2026-101986Junos OS and Junos OS Evolved: J-Web permits pre-authentication CGI execution
Critical 9.8
In plain English
A critical-severity improper authentication in Junos OS from Juniper Networks. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.5% (higher than 46% of all known vulnerabilities).
Severity (CVSS 3.1)9.8Critical
Exploit odds (30 days)0.5%top 53.8% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known
Official description
An Improper Authentication vulnerability in J-Web of Juniper Networks Junos OS and Junos OS Evolved allows an unauthenticated network attacker to bypass J-Web authentication and execute CGI content with elevated privileges via a crafted HTTP request.
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| Juniper Networks | Junos OS | 0 – before 23.2R2-S7.723.4 – before 23.4R2-S8.1324.2 – before 24.2R2-S5.524.4 – before 24.4R2-S525.2 – before 25.2R2-S225.4 – before 25.4R1-S326.2 – before 26.2R1-S2 |
| Juniper Networks | Junos OS Evolved | 0 – before 23.2R2-S7.7-EVO23.4 – before 23.4R2-S8.11-EVO24.2 – before 24.2R2-S5.6-EVO24.4 – before 24.4R2-S5-EVO25.2 – before 25.2R2-S2-EVO25.4 – before 25.4R1-S3-EVO26.2 – before 26.2R1-S2-EVO23.4X100 |
Weakness: CWE-287 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
References
- https://supportportal.juniper.net/JSA112187 vendor-advisory