CVE-2026-101951 Denial of service in Junos OS
A network-adjacent BGP peer can crash the routing daemon by sending a malformed multicast tree update, causing a denial of service.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-101951?
CVE-2026-101951 is a high-severity denial of service vulnerability in Juniper Networks Junos OS, published on 14 Oct 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
An Improper Validation of Consistency within Input vulnerability in the routing protocol daemon (rpd) of Juniper Networks Junos OS and Junos OS Evolved allows a network-adjacent configured BGP peer to cause a denial of service by sending a specifically malformed BGP MCAST-TREE update and this NLRI is then attempted to be readvertised.
Weakness: CWE-1288
Which versions are affected by CVE-2026-101951?
How do I fix CVE-2026-101951?
No fix has been published for CVE-2026-101951 yet. Limit exposure of the affected software until one is available.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2026-101951 being exploited?
There is no known exploitation of CVE-2026-101951 in the wild and no public exploit code.
Sources
Also known as GHSA-pqwq-mv6w-j3qf.