CVE-2026-101990 Junos OS and Junos OS Evolved: A BGP peer causes an rpd crash when flow-spec routes are re-advertised
A remote BGP peer can trigger a stack-based buffer overflow in the routing daemon, causing a crash or remote code execution on Junos OS devices.
- 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-2026-101990?
CVE-2026-101990 is a critical memory corruption 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
A Stack-based Buffer Overflow vulnerability in the routing protocol daemon (rpd) of Juniper Networks Junos OS and Junos OS Evolved allows a remote configured BGP peer to cause an rpd crash, or on Junos OS remote code-execution, via sending a flow-spec update which is selected for re-advertisement.
Weakness: CWE-121
Which versions are affected by CVE-2026-101990?
How do I fix CVE-2026-101990?
No fix has been published for CVE-2026-101990 yet. Limit exposure of the affected software until one is available.
Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.
Is CVE-2026-101990 being exploited?
There is no known exploitation of CVE-2026-101990 in the wild and no public exploit code.
Sources
Also known as GHSA-5vwc-cg2q-4mw8.