CVE-2026-101991 Junos OS and Junos OS Evolved: A BGP-LS peer causes heap data disclosure when traffic-engineering routing is enabled
A configured BGP-LS peer can disclose heap data by sending a malformed UPDATE when traffic-engineering routing is enabled.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-101991?
CVE-2026-101991 is a medium-severity vulnerability in Juniper Networks Junos OS, published on 14 Oct 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
An Improper Handling of Length Parameter Inconsistency vulnerability in the routing protocol daemon (rpd) of Juniper Networks Junos OS and Junos OS Evolved allows a configured BGP-LS peer to cause heap data disclosure via a malformed UPDATE sent over a session with the traffic-engineering address family enabled.
Weakness: CWE-130
Which versions are affected by CVE-2026-101991?
How do I fix CVE-2026-101991?
No fix has been published for CVE-2026-101991 yet. Limit exposure of the affected software until one is available.
Is CVE-2026-101991 being exploited?
There is no known exploitation of CVE-2026-101991 in the wild and no public exploit code.
Sources
Also known as GHSA-7hq3-vcv5-qgqv.