SB2026012064 - Use-after-free in Junos OS Evolved and Juniper Junos OS
Published: January 20, 2026
Security Bulletin ID
SB2026012064
Severity
Medium
Patch available
YES
Number of vulnerabilities
1
Exploitation vector
Adjecent network
Highest impact
Code execution
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 1 security vulnerability.
1) Use-after-free (CVE-ID: CVE-2026-21908)
The vulnerability allows a remote user to execute arbitrary code.
The vulnerability exists due to a use-after-free error in the 802.1X authentication daemon (dot1xd). A remote authenticated user can execute arbitrary code with elevated privileges.
This issue affects systems with 802.1X authentication port-based network access control (PNAC) enabled.
Remediation
Install update from vendor's website.