Use After Free in Juniper Junos
CVE-2026-21908
A Use After Free vulnerability was identified in the 802.1X authentication daemon (dot1xd) of Juniper Networks Junos OS and Junos OS Evolved that could allow an authenticated, network-adjacent attacker flapping a port to crash the dot1xd p…
Vulnerability class: Use-After-Free
EPSS: 0.003 (20.9th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 7.1 (High). Vector: CVSS:3.1/AV:A/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H.
Affected products
- Juniper Junos — versions 23.2, 23.4, 24.2
- Juniper Junos_os_evolved — versions 23.2, 23.4, 24.2
- Juniper Networks Junos Os — versions 23.2R2-S1, 23.4R2, 24.2
- Juniper Networks Junos Os Evolved — versions 23.2R2-S1, 23.4R2, 24.2
Weakness classification (CWE)
References
- sirt@juniper.net (vendor-advisory, Vendor Advisory)
- sirt@juniper.net (vendor-advisory, Vendor Advisory)
Frequently asked questions
- What is CVE-2026-21908?
- CVE-2026-21908 is a high-severity vulnerability in Juniper Junos, classified under Use After Free. CVSS score: 7.1/10. Published 2026-01-15.
- How severe is CVE-2026-21908?
- High severity. CVSS v3 base score is 7.1 out of 10.